diff --git a/django/test/_doctest.py b/django/test/_doctest.py
index 048d886720..c5b94c83a0 100644
--- a/django/test/_doctest.py
+++ b/django/test/_doctest.py
@@ -144,6 +144,8 @@ if sys.platform.startswith('java'):
 # Option constants.
 
 OPTIONFLAGS_BY_NAME = {}
+
+
 def register_optionflag(name):
     # Create a new flag unless `name` is already known.
     return OPTIONFLAGS_BY_NAME.setdefault(name, 1 << len(OPTIONFLAGS_BY_NAME))
@@ -194,6 +196,7 @@ ELLIPSIS_MARKER = '...'
 ## 1. Utility Functions
 ######################################################################
 
+
 def _extract_future_flags(globs):
     """
     Return the compiler-flags associated with the future features that
@@ -206,6 +209,7 @@ def _extract_future_flags(globs):
             flags |= feature.compiler_flag
     return flags
 
+
 def _normalize_module(module, depth=2):
     """
     Return the module specified by `module`.  In particular:
@@ -225,6 +229,7 @@ def _normalize_module(module, depth=2):
     else:
         raise TypeError("Expected a module, string, or None")
 
+
 def _load_testfile(filename, package, module_relative):
     if module_relative:
         package = _normalize_module(package, 3)
@@ -238,6 +243,7 @@ def _load_testfile(filename, package, module_relative):
     with open(filename) as fp:
         return fp.read(), filename
 
+
 def _indent(s, indent=4):
     """
     Add the given number of space characters to the beginning every
@@ -246,6 +252,7 @@ def _indent(s, indent=4):
     # This regexp matches the start of non-blank lines:
     return re.sub('(?m)^(?!$)', indent*' ', s)
 
+
 def _exception_traceback(exc_info):
     """
     Return a string containing a traceback message for the given
@@ -257,6 +264,7 @@ def _exception_traceback(exc_info):
     traceback.print_exception(exc_type, exc_val, exc_tb, file=excout)
     return excout.getvalue()
 
+
 # Override some StringIO methods.
 class _SpoofOut(StringIO):
     def getvalue(self):
@@ -277,6 +285,7 @@ class _SpoofOut(StringIO):
         if hasattr(self, "softspace"):
             del self.softspace
 
+
 # Worst-case linear-time ellipsis matching.
 def _ellipsis_match(want, got):
     """
@@ -327,6 +336,7 @@ def _ellipsis_match(want, got):
 
     return True
 
+
 def _comment_line(line):
     "Return a commented form of the given line"
     line = line.rstrip()
@@ -335,6 +345,7 @@ def _comment_line(line):
     else:
         return '#'
 
+
 class _OutputRedirectingPdb(pdb.Pdb):
     """
     A specialized version of the python debugger that redirects stdout
@@ -368,6 +379,7 @@ class _OutputRedirectingPdb(pdb.Pdb):
         finally:
             sys.stdout = save_stdout
 
+
 # [XX] Normalize with respect to os.path.pardir?
 def _module_relative_path(module, path):
     if not inspect.ismodule(module):
@@ -405,6 +417,7 @@ def _module_relative_path(module, path):
 ##   a string (such as an object's docstring).  The DocTest class also
 ##   includes information about where the string was extracted from.
 
+
 class Example:
     """
     A single doctest example, consisting of source code and expected
@@ -458,6 +471,7 @@ class Example:
         self.options = options
         self.exc_msg = exc_msg
 
+
 class DocTest:
     """
     A collection of doctest examples that should be run in a single
@@ -506,10 +520,10 @@ class DocTest:
         return ('<DocTest %s from %s:%s (%s)>' %
                 (self.name, self.filename, self.lineno, examples))
 
-
     # This lets us sort tests by name:
     def _cmpkey(self):
         return (self.name, self.filename, self.lineno, id(self))
+
     def __cmp__(self, other):
         if not isinstance(other, DocTest):
             return -1
@@ -1054,6 +1068,7 @@ class DocTestFinder:
 ## 5. DocTest Runner
 ######################################################################
 
+
 class DocTestRunner:
     """
     A class used to run DocTest test cases, and accumulate statistics.
@@ -1408,6 +1423,7 @@ class DocTestRunner:
     __LINECACHE_FILENAME_RE = re.compile(r'<doctest '
                                          r'(?P<name>[\w\.]+)'
                                          r'\[(?P<examplenum>\d+)\]>$')
+
     def __patched_linecache_getlines(self, filename, module_globals=None):
         m = self.__LINECACHE_FILENAME_RE.match(filename)
         if m and m.group('name') == self.test.name:
@@ -1541,6 +1557,7 @@ class DocTestRunner:
                 t = t + t2
             d[name] = f, t
 
+
 class OutputChecker:
     """
     A class used to check the whether the actual output from a doctest
@@ -1674,6 +1691,7 @@ class OutputChecker:
         else:
             return 'Expected nothing\nGot nothing\n'
 
+
 class DocTestFailure(Exception):
     """A DocTest example has failed in debugging mode.
 
@@ -1693,6 +1711,7 @@ class DocTestFailure(Exception):
     def __str__(self):
         return str(self.test)
 
+
 class UnexpectedException(Exception):
     """A DocTest example has encountered an unexpected exception
 
@@ -1712,6 +1731,7 @@ class UnexpectedException(Exception):
     def __str__(self):
         return str(self.test)
 
+
 class DebugRunner(DocTestRunner):
     r"""Run doc tests but raise an exception as soon as there is a failure.
 
@@ -1824,6 +1844,7 @@ class DebugRunner(DocTestRunner):
 # class, updated by testmod.
 master = None
 
+
 def testmod(m=None, name=None, globs=None, verbose=None,
             report=True, optionflags=0, extraglobs=None,
             raise_on_error=False, exclude_empty=False):
@@ -1928,6 +1949,7 @@ def testmod(m=None, name=None, globs=None, verbose=None,
 
     return runner.failures, runner.tries
 
+
 def testfile(filename, module_relative=True, name=None, package=None,
              globs=None, verbose=None, report=True, optionflags=0,
              extraglobs=None, raise_on_error=False, parser=DocTestParser(),
@@ -2051,6 +2073,7 @@ def testfile(filename, module_relative=True, name=None, package=None,
 
     return runner.failures, runner.tries
 
+
 def run_docstring_examples(f, globs, verbose=False, name="NoName",
                            compileflags=None, optionflags=0):
     """
@@ -2080,6 +2103,7 @@ def run_docstring_examples(f, globs, verbose=False, name="NoName",
 # This is provided only for backwards compatibility.  It's not
 # actually used in any way.
 
+
 class Tester:
     def __init__(self, mod=None, globs=None, verbose=None, optionflags=0):
 
@@ -2145,6 +2169,7 @@ class Tester:
 
 _unittest_reportflags = 0
 
+
 def set_unittest_reportflags(flags):
     """Sets the unittest option flags.
 
@@ -2328,6 +2353,7 @@ class DocTestCase(unittest.TestCase):
     def shortDescription(self):
         return "Doctest: " + self._dt_test.name
 
+
 def DocTestSuite(module=None, globs=None, extraglobs=None, test_finder=None,
                  test_class=DocTestCase, **options):
     """
@@ -2391,6 +2417,7 @@ def DocTestSuite(module=None, globs=None, extraglobs=None, test_finder=None,
 
     return suite
 
+
 class DocFileCase(DocTestCase):
 
     def id(self):
@@ -2405,6 +2432,7 @@ class DocFileCase(DocTestCase):
                 % (self._dt_test.name, self._dt_test.filename, err)
                 )
 
+
 def DocFileTest(path, module_relative=True, package=None,
                 globs=None, parser=DocTestParser(),
                 encoding=None, **options):
@@ -2434,6 +2462,7 @@ def DocFileTest(path, module_relative=True, package=None,
     test = parser.get_doctest(doc, globs, name, path, 0)
     return DocFileCase(test, **options)
 
+
 def DocFileSuite(*paths, **kw):
     """A unittest suite for one or more doctest files.
 
@@ -2507,6 +2536,7 @@ def DocFileSuite(*paths, **kw):
 ## 9. Debugging Support
 ######################################################################
 
+
 def script_from_examples(s):
     r"""Extract script from text with examples.
 
@@ -2587,6 +2617,7 @@ def script_from_examples(s):
     # Combine the output, and return it.
     return '\n'.join(output)
 
+
 def testsource(module, name):
     """Extract the test sources from a doctest docstring as a script.
 
@@ -2603,11 +2634,13 @@ def testsource(module, name):
     testsrc = script_from_examples(test.docstring)
     return testsrc
 
+
 def debug_src(src, pm=False, globs=None):
     """Debug a single doctest docstring, in argument `src`'"""
     testsrc = script_from_examples(src)
     debug_script(testsrc, pm, globs)
 
+
 def debug_script(src, pm=False, globs=None):
     "Debug a test script.  `src` is the script, as a string."
     import pdb
@@ -2639,6 +2672,7 @@ def debug_script(src, pm=False, globs=None):
     finally:
         os.remove(srcfilename)
 
+
 def debug(module, name, pm=False):
     """Debug a single doctest docstring.
 
@@ -2653,6 +2687,8 @@ def debug(module, name, pm=False):
 ######################################################################
 ## 10. Example Usage
 ######################################################################
+
+
 class _TestClass:
     """
     A pointless class, for sanity-checking of docstring testing.
@@ -2747,6 +2783,7 @@ __test__ = {"_TestClass": _TestClass,
             """,
            }
 
+
 def _test():
     r = unittest.TextTestRunner()
     r.run(DocTestSuite())
diff --git a/django/test/testcases.py b/django/test/testcases.py
index 3fed8c6aa7..fa044ba6ec 100644
--- a/django/test/testcases.py
+++ b/django/test/testcases.py
@@ -61,9 +61,11 @@ real_enter_transaction_management = transaction.enter_transaction_management
 real_leave_transaction_management = transaction.leave_transaction_management
 real_abort = transaction.abort
 
+
 def nop(*args, **kwargs):
     return
 
+
 def disable_transaction_methods():
     transaction.commit = nop
     transaction.rollback = nop
@@ -71,6 +73,7 @@ def disable_transaction_methods():
     transaction.leave_transaction_management = nop
     transaction.abort = nop
 
+
 def restore_transaction_methods():
     transaction.commit = real_commit
     transaction.rollback = real_rollback
diff --git a/django/utils/_os.py b/django/utils/_os.py
index 40a8e278fc..11fc5afe49 100644
--- a/django/utils/_os.py
+++ b/django/utils/_os.py
@@ -53,6 +53,7 @@ def npath(path):
         return path.encode(fs_encoding)
     return path
 
+
 def safe_join(base, *paths):
     """
     Joins one or more path components to the base path component intelligently.
diff --git a/django/utils/autoreload.py b/django/utils/autoreload.py
index ca162d18d0..00f7ce160a 100644
--- a/django/utils/autoreload.py
+++ b/django/utils/autoreload.py
@@ -119,6 +119,7 @@ def gen_filenames():
         if os.path.exists(filename):
             yield filename
 
+
 def inotify_code_changed():
     """
     Checks for changed code using inotify. After being called
@@ -149,6 +150,7 @@ def inotify_code_changed():
     # If we are here the code must have changed.
     return True
 
+
 def kqueue_code_changed():
     """
     Checks for changed code using kqueue. After being called
@@ -193,6 +195,7 @@ def kqueue_code_changed():
 
     return True
 
+
 def code_changed():
     global _mtimes, _win
     for filename in gen_filenames():
@@ -212,6 +215,7 @@ def code_changed():
             return True
     return False
 
+
 def check_errors(fn):
     def wrapper(*args, **kwargs):
         try:
@@ -233,6 +237,7 @@ def check_errors(fn):
 
     return wrapper
 
+
 def ensure_echo_on():
     if termios:
         fd = sys.stdin
@@ -248,6 +253,7 @@ def ensure_echo_on():
                 if old_handler is not None:
                     signal.signal(signal.SIGTTOU, old_handler)
 
+
 def reloader_thread():
     ensure_echo_on()
     if USE_INOTIFY:
@@ -273,6 +279,7 @@ def restart_with_reloader():
         if exit_code != 3:
             return exit_code
 
+
 def python_reloader(main_func, args, kwargs):
     if os.environ.get("RUN_MAIN") == "true":
         thread.start_new_thread(main_func, args, kwargs)
@@ -290,6 +297,7 @@ def python_reloader(main_func, args, kwargs):
         except KeyboardInterrupt:
             pass
 
+
 def jython_reloader(main_func, args, kwargs):
     from _systemrestart import SystemRestart
     thread.start_new_thread(main_func, args)
diff --git a/django/utils/cache.py b/django/utils/cache.py
index 0d664afdf4..7e38f7b021 100644
--- a/django/utils/cache.py
+++ b/django/utils/cache.py
@@ -31,6 +31,7 @@ from django.utils.translation import get_language
 
 cc_delim_re = re.compile(r'\s*,\s*')
 
+
 def patch_cache_control(response, **kwargs):
     """
     This function patches the Cache-Control header by adding all
@@ -79,6 +80,7 @@ def patch_cache_control(response, **kwargs):
     cc = ', '.join(dictvalue(el) for el in cc.items())
     response['Cache-Control'] = cc
 
+
 def get_max_age(response):
     """
     Returns the max-age from the response Cache-Control header as an integer
@@ -94,11 +96,13 @@ def get_max_age(response):
         except (ValueError, TypeError):
             pass
 
+
 def _set_response_etag(response):
     if not response.streaming:
         response['ETag'] = '"%s"' % hashlib.md5(response.content).hexdigest()
     return response
 
+
 def patch_response_headers(response, cache_timeout=None):
     """
     Adds some useful headers to the given HttpResponse object:
@@ -124,12 +128,14 @@ def patch_response_headers(response, cache_timeout=None):
         response['Expires'] = http_date(time.time() + cache_timeout)
     patch_cache_control(response, max_age=cache_timeout)
 
+
 def add_never_cache_headers(response):
     """
     Adds headers to a response to indicate that a page should never be cached.
     """
     patch_response_headers(response, cache_timeout=-1)
 
+
 def patch_vary_headers(response, newheaders):
     """
     Adds (or updates) the "Vary" header in the given HttpResponse object.
@@ -149,6 +155,7 @@ def patch_vary_headers(response, newheaders):
                           if newheader.lower() not in existing_headers]
     response['Vary'] = ', '.join(vary_headers + additional_headers)
 
+
 def has_vary_header(response, header_query):
     """
     Checks to see if the response has a given header name in its Vary header.
@@ -159,6 +166,7 @@ def has_vary_header(response, header_query):
     existing_headers = set(header.lower() for header in vary_headers)
     return header_query.lower() in existing_headers
 
+
 def _i18n_cache_key_suffix(request, cache_key):
     """If necessary, adds the current locale or time zone to the cache key."""
     if settings.USE_I18N or settings.USE_L10N:
@@ -175,6 +183,7 @@ def _i18n_cache_key_suffix(request, cache_key):
         cache_key += '.%s' % tz_name.encode('ascii', 'ignore').decode('ascii').replace(' ', '_')
     return cache_key
 
+
 def _generate_cache_key(request, method, headerlist, key_prefix):
     """Returns a cache key from the headers given in the header list."""
     ctx = hashlib.md5()
@@ -187,6 +196,7 @@ def _generate_cache_key(request, method, headerlist, key_prefix):
         key_prefix, method, path.hexdigest(), ctx.hexdigest())
     return _i18n_cache_key_suffix(request, cache_key)
 
+
 def _generate_cache_header_key(key_prefix, request):
     """Returns a cache key for the header cache."""
     path = hashlib.md5(force_bytes(iri_to_uri(request.get_full_path())))
@@ -194,6 +204,7 @@ def _generate_cache_header_key(key_prefix, request):
         key_prefix, path.hexdigest())
     return _i18n_cache_key_suffix(request, cache_key)
 
+
 def get_cache_key(request, key_prefix=None, method='GET', cache=None):
     """
     Returns a cache key based on the request path and query. It can be used
@@ -215,6 +226,7 @@ def get_cache_key(request, key_prefix=None, method='GET', cache=None):
     else:
         return None
 
+
 def learn_cache_key(request, response, cache_timeout=None, key_prefix=None, cache=None):
     """
     Learns what headers to take into account for some request path from the
diff --git a/django/utils/datastructures.py b/django/utils/datastructures.py
index e5fe4a776a..49855dd33b 100644
--- a/django/utils/datastructures.py
+++ b/django/utils/datastructures.py
@@ -3,6 +3,7 @@ import warnings
 from collections import OrderedDict
 from django.utils import six
 
+
 class MergeDict(object):
     """
     A simple class for creating new "virtual" dictionaries that actually look
@@ -117,6 +118,7 @@ class MergeDict(object):
         dictreprs = ', '.join(repr(d) for d in self.dicts)
         return '%s(%s)' % (self.__class__.__name__, dictreprs)
 
+
 class SortedDict(dict):
     """
     A dictionary that keeps its keys in the order in which they're inserted.
@@ -239,6 +241,7 @@ class SortedDict(dict):
         super(SortedDict, self).clear()
         self.keyOrder = []
 
+
 class OrderedSet(object):
     """
     A set which keeps the ordering of the inserted items.
@@ -269,9 +272,11 @@ class OrderedSet(object):
     def __nonzero__(self):
         return bool(self.dict)
 
+
 class MultiValueDictKeyError(KeyError):
     pass
 
+
 class MultiValueDict(dict):
     """
     A subclass of dictionary customized to handle multiple values for the
@@ -504,6 +509,7 @@ class ImmutableList(tuple):
     sort = complain
     reverse = complain
 
+
 class DictWrapper(dict):
     """
     Wraps accesses to a dictionary so that certain values (those starting with
diff --git a/django/utils/dateformat.py b/django/utils/dateformat.py
index 27413a2e67..78483f2d4c 100644
--- a/django/utils/dateformat.py
+++ b/django/utils/dateformat.py
@@ -26,6 +26,7 @@ from django.utils.timezone import get_default_timezone, is_aware, is_naive
 re_formatchars = re.compile(r'(?<!\\)([aAbBcdDeEfFgGhHiIjlLmMnNoOPrsStTUuwWyYzZ])')
 re_escaped = re.compile(r'\\(.)')
 
+
 class Formatter(object):
     def format(self, formatstr):
         pieces = []
@@ -36,6 +37,7 @@ class Formatter(object):
                 pieces.append(re_escaped.sub(r'\1', piece))
         return ''.join(pieces)
 
+
 class TimeFormat(Formatter):
 
     def __init__(self, obj):
diff --git a/django/utils/dateparse.py b/django/utils/dateparse.py
index 1e2cad7d01..f2c079023f 100644
--- a/django/utils/dateparse.py
+++ b/django/utils/dateparse.py
@@ -39,6 +39,7 @@ def parse_date(value):
         kw = dict((k, int(v)) for k, v in six.iteritems(match.groupdict()))
         return datetime.date(**kw)
 
+
 def parse_time(value):
     """Parses a string and return a datetime.time.
 
@@ -56,6 +57,7 @@ def parse_time(value):
         kw = dict((k, int(v)) for k, v in six.iteritems(kw) if v is not None)
         return datetime.time(**kw)
 
+
 def parse_datetime(value):
     """Parses a string and return a datetime.datetime.
 
diff --git a/django/utils/datetime_safe.py b/django/utils/datetime_safe.py
index 6aa32f30bf..a584011db5 100644
--- a/django/utils/datetime_safe.py
+++ b/django/utils/datetime_safe.py
@@ -30,10 +30,12 @@ class datetime(real_datetime):
     def date(self):
         return date(self.year, self.month, self.day)
 
+
 def new_date(d):
     "Generate a safe date from a datetime.date object."
     return date(d.year, d.month, d.day)
 
+
 def new_datetime(d):
     """
     Generate a safe datetime from a datetime.date or datetime.datetime object.
@@ -47,6 +49,7 @@ def new_datetime(d):
 # Allowed if there's an even number of "%"s because they are escaped.
 _illegal_formatting = re.compile(r"((^|[^%])(%%)*%[sy])")
 
+
 def _findall(text, substr):
     # Also finds overlaps
     sites = []
@@ -59,6 +62,7 @@ def _findall(text, substr):
         i = j + 1
     return sites
 
+
 def strftime(dt, fmt):
     if dt.year >= 1900:
         return super(type(dt), dt).strftime(fmt)
diff --git a/django/utils/dictconfig.py b/django/utils/dictconfig.py
index 773b703497..e79dc041ef 100644
--- a/django/utils/dictconfig.py
+++ b/django/utils/dictconfig.py
@@ -32,6 +32,7 @@ from django.utils import six
 
 IDENTIFIER = re.compile('^[a-z_][a-z0-9_]*$', re.I)
 
+
 def valid_ident(s):
     m = IDENTIFIER.match(s)
     if not m:
@@ -65,6 +66,7 @@ except ImportError:
 # Each wrapper should have a configurator attribute holding the actual
 # configurator to use for conversion.
 
+
 class ConvertingDict(dict):
     """A converting dictionary wrapper."""
 
@@ -102,6 +104,7 @@ class ConvertingDict(dict):
                 result.key = key
         return result
 
+
 class ConvertingList(list):
     """A converting list wrapper."""
     def __getitem__(self, key):
@@ -125,6 +128,7 @@ class ConvertingList(list):
                 result.parent = self
         return result
 
+
 class ConvertingTuple(tuple):
     """A converting tuple wrapper."""
     def __getitem__(self, key):
@@ -137,6 +141,7 @@ class ConvertingTuple(tuple):
                 result.key = key
         return result
 
+
 class BaseConfigurator(object):
     """
     The configurator base class which defines some useful defaults.
@@ -270,6 +275,7 @@ class BaseConfigurator(object):
             value = tuple(value)
         return value
 
+
 class DictConfigurator(BaseConfigurator):
     """
     Configure logging using a dictionary-like object to describe the
@@ -555,6 +561,7 @@ class DictConfigurator(BaseConfigurator):
 
 dictConfigClass = DictConfigurator
 
+
 def dictConfig(config):
     """Configure logging using a dictionary."""
     dictConfigClass(config).configure()
diff --git a/django/utils/encoding.py b/django/utils/encoding.py
index ad4473df6a..ee67df30ea 100644
--- a/django/utils/encoding.py
+++ b/django/utils/encoding.py
@@ -38,6 +38,7 @@ def python_2_unicode_compatible(klass):
         klass.__str__ = lambda self: self.__unicode__().encode('utf-8')
     return klass
 
+
 def smart_text(s, encoding='utf-8', strings_only=False, errors='strict'):
     """
     Returns a text object representing 's' -- unicode on Python 2 and str on
@@ -50,6 +51,7 @@ def smart_text(s, encoding='utf-8', strings_only=False, errors='strict'):
         return s
     return force_text(s, encoding, strings_only, errors)
 
+
 def is_protected_type(obj):
     """Determine if the object instance is of a protected type.
 
@@ -59,6 +61,7 @@ def is_protected_type(obj):
     return isinstance(obj, six.integer_types + (type(None), float, Decimal,
         datetime.datetime, datetime.date, datetime.time))
 
+
 def force_text(s, encoding='utf-8', strings_only=False, errors='strict'):
     """
     Similar to smart_text, except that lazy instances are resolved to
@@ -100,6 +103,7 @@ def force_text(s, encoding='utf-8', strings_only=False, errors='strict'):
                     errors) for arg in s])
     return s
 
+
 def smart_bytes(s, encoding='utf-8', strings_only=False, errors='strict'):
     """
     Returns a bytestring version of 's', encoded as specified in 'encoding'.
@@ -168,6 +172,7 @@ force_str.__doc__ = """
 Apply force_text in Python 3 and force_bytes in Python 2.
 """
 
+
 def iri_to_uri(iri):
     """
     Convert an Internationalized Resource Identifier (IRI) portion to a URI
@@ -195,6 +200,7 @@ def iri_to_uri(iri):
         return iri
     return quote(force_bytes(iri), safe=b"/#%[]=:;$&()+,!?*@'~")
 
+
 def filepath_to_uri(path):
     """Convert a file system path to a URI portion that is suitable for
     inclusion in a URL.
@@ -214,6 +220,7 @@ def filepath_to_uri(path):
     # some flexibility for hardcoding separators.
     return quote(force_bytes(path).replace(b"\\", b"/"), safe=b"/~!*()'")
 
+
 def get_system_encoding():
     """
     The encoding of the default system locale but falls back to the given
diff --git a/django/utils/feedgenerator.py b/django/utils/feedgenerator.py
index 416234521f..00d982025a 100644
--- a/django/utils/feedgenerator.py
+++ b/django/utils/feedgenerator.py
@@ -54,6 +54,7 @@ def rfc2822_date(date):
     else:
         return time_str + '-0000'
 
+
 def rfc3339_date(date):
     # Support datetime objects older than 1900
     date = datetime_safe.new_datetime(date)
@@ -68,6 +69,7 @@ def rfc3339_date(date):
     else:
         return time_str + 'Z'
 
+
 def get_tag_uri(url, date):
     """
     Creates a TagURI.
@@ -80,6 +82,7 @@ def get_tag_uri(url, date):
         d = ',%s' % datetime_safe.new_datetime(date).strftime('%Y-%m-%d')
     return 'tag:%s%s:%s/%s' % (bits.hostname, d, bits.path, bits.fragment)
 
+
 class SyndicationFeed(object):
     "Base class for all syndication feeds. Subclasses should provide write()"
     def __init__(self, title, link, description, language=None, author_email=None,
@@ -205,6 +208,7 @@ class SyndicationFeed(object):
 
         return latest_date or datetime.datetime.now()
 
+
 class Enclosure(object):
     "Represents an RSS enclosure"
     def __init__(self, url, length, mime_type):
@@ -212,6 +216,7 @@ class Enclosure(object):
         self.length, self.mime_type = length, mime_type
         self.url = iri_to_uri(url)
 
+
 class RssFeed(SyndicationFeed):
     mime_type = 'application/rss+xml; charset=utf-8'
 
@@ -255,6 +260,7 @@ class RssFeed(SyndicationFeed):
     def endChannelElement(self, handler):
         handler.endElement("channel")
 
+
 class RssUserland091Feed(RssFeed):
     _version = "0.91"
 
@@ -264,6 +270,7 @@ class RssUserland091Feed(RssFeed):
         if item['description'] is not None:
             handler.addQuickElement("description", item['description'])
 
+
 class Rss201rev2Feed(RssFeed):
     # Spec: http://blogs.law.harvard.edu/tech/rss
     _version = "2.0"
@@ -306,6 +313,7 @@ class Rss201rev2Feed(RssFeed):
         for cat in item['categories']:
             handler.addQuickElement("category", cat)
 
+
 class Atom1Feed(SyndicationFeed):
     # Spec: http://atompub.org/2005/07/11/draft-ietf-atompub-format-10.html
     mime_type = 'application/atom+xml; charset=utf-8'
diff --git a/django/utils/formats.py b/django/utils/formats.py
index 0c59e2c04a..fc68179f3a 100644
--- a/django/utils/formats.py
+++ b/django/utils/formats.py
@@ -30,6 +30,7 @@ ISO_INPUT_FORMATS = {
     ),
 }
 
+
 def reset_format_cache():
     """Clear any cached formats.
 
@@ -40,6 +41,7 @@ def reset_format_cache():
     _format_cache = {}
     _format_modules_cache = {}
 
+
 def iter_format_modules(lang, format_module_path=None):
     """
     Does the heavy lifting of finding format modules.
@@ -60,6 +62,7 @@ def iter_format_modules(lang, format_module_path=None):
                 except ImportError:
                     pass
 
+
 def get_format_modules(lang=None, reverse=False):
     """
     Returns a list of the format modules found
@@ -71,6 +74,7 @@ def get_format_modules(lang=None, reverse=False):
         return list(reversed(modules))
     return modules
 
+
 def get_format(format_type, lang=None, use_l10n=None):
     """
     For a specific format type, returns the format for the current
@@ -110,6 +114,7 @@ def get_format(format_type, lang=None, use_l10n=None):
 
 get_format_lazy = lazy(get_format, six.text_type, list, tuple)
 
+
 def date_format(value, format=None, use_l10n=None):
     """
     Formats a datetime.date or datetime.datetime object using a
@@ -120,6 +125,7 @@ def date_format(value, format=None, use_l10n=None):
     """
     return dateformat.format(value, get_format(format or 'DATE_FORMAT', use_l10n=use_l10n))
 
+
 def time_format(value, format=None, use_l10n=None):
     """
     Formats a datetime.time object using a localizable format
@@ -129,6 +135,7 @@ def time_format(value, format=None, use_l10n=None):
     """
     return dateformat.time_format(value, get_format(format or 'TIME_FORMAT', use_l10n=use_l10n))
 
+
 def number_format(value, decimal_pos=None, use_l10n=None, force_grouping=False):
     """
     Formats a numeric value using localization settings
@@ -149,6 +156,7 @@ def number_format(value, decimal_pos=None, use_l10n=None, force_grouping=False):
         force_grouping=force_grouping
     )
 
+
 def localize(value, use_l10n=None):
     """
     Checks if value is a localizable type (date, number...) and returns it
@@ -170,6 +178,7 @@ def localize(value, use_l10n=None):
     else:
         return value
 
+
 def localize_input(value, default=None):
     """
     Checks if an input value is a localizable type and returns it
@@ -190,6 +199,7 @@ def localize_input(value, default=None):
         return value.strftime(format)
     return value
 
+
 def sanitize_separators(value):
     """
     Sanitizes a value according to the current decimal and
diff --git a/django/utils/html.py b/django/utils/html.py
index 6d04ae5205..3ad549de19 100644
--- a/django/utils/html.py
+++ b/django/utils/html.py
@@ -72,6 +72,7 @@ def conditional_escape(text):
     else:
         return escape(text)
 
+
 def format_html(format_string, *args, **kwargs):
     """
     Similar to str.format, but passes all arguments through conditional_escape,
@@ -83,6 +84,7 @@ def format_html(format_string, *args, **kwargs):
                         six.iteritems(kwargs))
     return mark_safe(format_string.format(*args_safe, **kwargs_safe))
 
+
 def format_html_join(sep, format_string, args_generator):
     """
     A wrapper of format_html, for the common case of a group of arguments that
@@ -133,6 +135,7 @@ class MLStripper(HTMLParser):
     def get_data(self):
         return ''.join(self.fed)
 
+
 def strip_tags(value):
     """Returns the given HTML with all tags stripped."""
     s = MLStripper()
@@ -145,6 +148,7 @@ def strip_tags(value):
         return s.get_data()
 strip_tags = allow_lazy(strip_tags)
 
+
 def remove_tags(html, tags):
     """Returns the given HTML with given tags removed."""
     tags = [re.escape(tag) for tag in tags.split()]
@@ -156,21 +160,25 @@ def remove_tags(html, tags):
     return html
 remove_tags = allow_lazy(remove_tags, six.text_type)
 
+
 def strip_spaces_between_tags(value):
     """Returns the given HTML with spaces between tags removed."""
     return re.sub(r'>\s+<', '><', force_text(value))
 strip_spaces_between_tags = allow_lazy(strip_spaces_between_tags, six.text_type)
 
+
 def strip_entities(value):
     """Returns the given HTML with all entities (&something;) stripped."""
     return re.sub(r'&(?:\w+|#\d+);', '', force_text(value))
 strip_entities = allow_lazy(strip_entities, six.text_type)
 
+
 def fix_ampersands(value):
     """Returns the given HTML with all unencoded ampersands encoded correctly."""
     return unencoded_ampersands_re.sub('&amp;', force_text(value))
 fix_ampersands = allow_lazy(fix_ampersands, six.text_type)
 
+
 def smart_urlquote(url):
     "Quotes a URL if it isn't already quoted."
     # Handle IDN before quoting.
@@ -192,6 +200,7 @@ def smart_urlquote(url):
 
     return force_text(url)
 
+
 def urlize(text, trim_url_limit=None, nofollow=False, autoescape=False):
     """
     Converts any URLs in text into clickable links.
@@ -269,6 +278,7 @@ def urlize(text, trim_url_limit=None, nofollow=False, autoescape=False):
     return ''.join(words)
 urlize = allow_lazy(urlize, six.text_type)
 
+
 def clean_html(text):
     """
     Clean the given HTML.  Specifically, do the following:
@@ -304,6 +314,7 @@ def clean_html(text):
     return text
 clean_html = allow_lazy(clean_html, six.text_type)
 
+
 def avoid_wrapping(value):
     """
     Avoid text wrapping in the middle of a phrase by adding non-breaking
diff --git a/django/utils/http.py b/django/utils/http.py
index 413ac72a08..e3365776f3 100644
--- a/django/utils/http.py
+++ b/django/utils/http.py
@@ -30,6 +30,7 @@ RFC1123_DATE = re.compile(r'^\w{3}, %s %s %s %s GMT$' % (__D, __M, __Y, __T))
 RFC850_DATE = re.compile(r'^\w{6,9}, %s-%s-%s %s GMT$' % (__D, __M, __Y2, __T))
 ASCTIME_DATE = re.compile(r'^\w{3} %s %s %s %s$' % (__M, __D2, __T, __Y))
 
+
 def urlquote(url, safe='/'):
     """
     A version of Python's urllib.quote() function that can operate on unicode
@@ -40,6 +41,7 @@ def urlquote(url, safe='/'):
     return force_text(quote(force_str(url), force_str(safe)))
 urlquote = allow_lazy(urlquote, six.text_type)
 
+
 def urlquote_plus(url, safe=''):
     """
     A version of Python's urllib.quote_plus() function that can operate on
@@ -50,6 +52,7 @@ def urlquote_plus(url, safe=''):
     return force_text(quote_plus(force_str(url), force_str(safe)))
 urlquote_plus = allow_lazy(urlquote_plus, six.text_type)
 
+
 def urlunquote(quoted_url):
     """
     A wrapper for Python's urllib.unquote() function that can operate on
@@ -58,6 +61,7 @@ def urlunquote(quoted_url):
     return force_text(unquote(force_str(quoted_url)))
 urlunquote = allow_lazy(urlunquote, six.text_type)
 
+
 def urlunquote_plus(quoted_url):
     """
     A wrapper for Python's urllib.unquote_plus() function that can operate on
@@ -66,6 +70,7 @@ def urlunquote_plus(quoted_url):
     return force_text(unquote_plus(force_str(quoted_url)))
 urlunquote_plus = allow_lazy(urlunquote_plus, six.text_type)
 
+
 def urlencode(query, doseq=0):
     """
     A version of Python's urllib.urlencode() function that can operate on
@@ -82,6 +87,7 @@ def urlencode(query, doseq=0):
             for k, v in query],
         doseq)
 
+
 def cookie_date(epoch_seconds=None):
     """
     Formats the time to ensure compatibility with Netscape's cookie standard.
@@ -95,6 +101,7 @@ def cookie_date(epoch_seconds=None):
     rfcdate = formatdate(epoch_seconds)
     return '%s-%s-%s GMT' % (rfcdate[:7], rfcdate[8:11], rfcdate[12:25])
 
+
 def http_date(epoch_seconds=None):
     """
     Formats the time to match the RFC1123 date format as specified by HTTP
@@ -108,6 +115,7 @@ def http_date(epoch_seconds=None):
     """
     return formatdate(epoch_seconds, usegmt=True)
 
+
 def parse_http_date(date):
     """
     Parses a date format as specified by HTTP RFC2616 section 3.3.1.
@@ -143,6 +151,7 @@ def parse_http_date(date):
     except Exception:
         six.reraise(ValueError, ValueError("%r is not a valid date" % date), sys.exc_info()[2])
 
+
 def parse_http_date_safe(date):
     """
     Same as parse_http_date, but returns None if the input is invalid.
@@ -152,6 +161,7 @@ def parse_http_date_safe(date):
     except Exception:
         pass
 
+
 # Base 36 functions: useful for generating compact URLs
 
 def base36_to_int(s):
@@ -171,6 +181,7 @@ def base36_to_int(s):
         raise ValueError("Base36 input too large")
     return value
 
+
 def int_to_base36(i):
     """
     Converts an integer to a base36 string
@@ -199,6 +210,7 @@ def int_to_base36(i):
         factor -= 1
     return ''.join(base36)
 
+
 def urlsafe_base64_encode(s):
     """
     Encodes a bytestring in base64 for use in URLs, stripping any trailing
@@ -206,6 +218,7 @@ def urlsafe_base64_encode(s):
     """
     return base64.urlsafe_b64encode(s).rstrip(b'\n=')
 
+
 def urlsafe_base64_decode(s):
     """
     Decodes a base64 encoded string, adding back any trailing equal signs that
@@ -217,6 +230,7 @@ def urlsafe_base64_decode(s):
     except (LookupError, BinasciiError) as e:
         raise ValueError(e)
 
+
 def parse_etags(etag_str):
     """
     Parses a string with one or several etags passed in If-None-Match and
@@ -230,12 +244,14 @@ def parse_etags(etag_str):
     etags = [e.encode('ascii').decode('unicode_escape') for e in etags]
     return etags
 
+
 def quote_etag(etag):
     """
     Wraps a string in double quotes escaping contents as necessary.
     """
     return '"%s"' % etag.replace('\\', '\\\\').replace('"', '\\"')
 
+
 def same_origin(url1, url2):
     """
     Checks if two URLs are 'same-origin'
@@ -246,6 +262,7 @@ def same_origin(url1, url2):
     except ValueError:
         return False
 
+
 def is_safe_url(url, host=None):
     """
     Return ``True`` if the url is a safe redirection (i.e. it doesn't point to
diff --git a/django/utils/regex_helper.py b/django/utils/regex_helper.py
index c8390cc7eb..199b4ea87d 100644
--- a/django/utils/regex_helper.py
+++ b/django/utils/regex_helper.py
@@ -202,6 +202,7 @@ def normalize(pattern):
 
     return list(zip(*flatten_result(result)))
 
+
 def next_char(input_iter):
     """
     An iterator that yields the next character from "pattern_iter", respecting
@@ -222,6 +223,7 @@ def next_char(input_iter):
             continue
         yield representative, True
 
+
 def walk_to_end(ch, input_iter):
     """
     The iterator is currently inside a capturing group. We want to walk to the
@@ -242,6 +244,7 @@ def walk_to_end(ch, input_iter):
                 return
             nesting -= 1
 
+
 def get_quantifier(ch, input_iter):
     """
     Parse a quantifier from the input, where "ch" is the first character in the
@@ -278,6 +281,7 @@ def get_quantifier(ch, input_iter):
         ch = None
     return int(values[0]), ch
 
+
 def contains(source, inst):
     """
     Returns True if the "source" contains an instance of "inst". False,
@@ -291,6 +295,7 @@ def contains(source, inst):
                 return True
     return False
 
+
 def flatten_result(source):
     """
     Turns the given source sequence into a list of reg-exp possibilities and
diff --git a/django/utils/safestring.py b/django/utils/safestring.py
index c44726090f..097d31dd0f 100644
--- a/django/utils/safestring.py
+++ b/django/utils/safestring.py
@@ -32,6 +32,7 @@ else:
     # backwards compatibility for Python 2
     EscapeUnicode = EscapeText
 
+
 class SafeData(object):
     def __html__(self):
         """
@@ -41,6 +42,7 @@ class SafeData(object):
         """
         return self
 
+
 class SafeBytes(bytes, SafeData):
     """
     A bytes subclass that has been specifically marked as "safe" (requires no
@@ -75,6 +77,7 @@ class SafeBytes(bytes, SafeData):
 
     decode = curry(_proxy_method, method=bytes.decode)
 
+
 class SafeText(six.text_type, SafeData):
     """
     A unicode (Python 2) / str (Python 3) subclass that has been specifically
@@ -114,6 +117,7 @@ else:
     # backwards compatibility for Python 2
     SafeUnicode = SafeText
 
+
 def mark_safe(s):
     """
     Explicitly mark a string as safe for (HTML) output purposes. The returned
@@ -129,6 +133,7 @@ def mark_safe(s):
         return SafeText(s)
     return SafeString(str(s))
 
+
 def mark_for_escaping(s):
     """
     Explicitly mark a string as requiring HTML escaping upon output. Has no
diff --git a/django/utils/six.py b/django/utils/six.py
index 7abefb2258..b9d311499b 100644
--- a/django/utils/six.py
+++ b/django/utils/six.py
@@ -428,14 +428,17 @@ def iterkeys(d, **kw):
     """Return an iterator over the keys of a dictionary."""
     return iter(getattr(d, _iterkeys)(**kw))
 
+
 def itervalues(d, **kw):
     """Return an iterator over the values of a dictionary."""
     return iter(getattr(d, _itervalues)(**kw))
 
+
 def iteritems(d, **kw):
     """Return an iterator over the (key, value) pairs of a dictionary."""
     return iter(getattr(d, _iteritems)(**kw))
 
+
 def iterlists(d, **kw):
     """Return an iterator over the (key, [values]) pairs of a dictionary."""
     return iter(getattr(d, _iterlists)(**kw))
@@ -565,6 +568,7 @@ def with_metaclass(meta, *bases):
     """Create a base class with a metaclass."""
     return meta("NewBase", bases, {})
 
+
 def add_metaclass(metaclass):
     """Class decorator for creating a class with a metaclass."""
     def wrapper(cls):
diff --git a/django/utils/text.py b/django/utils/text.py
index 8f20e8ed88..bb05afefc4 100644
--- a/django/utils/text.py
+++ b/django/utils/text.py
@@ -209,6 +209,7 @@ class Truncator(SimpleLazyObject):
         # Return string
         return out
 
+
 def get_valid_filename(s):
     """
     Returns the given string converted to a string that can be used for a clean
@@ -222,6 +223,7 @@ def get_valid_filename(s):
     return re.sub(r'(?u)[^-\w.]', '', s)
 get_valid_filename = allow_lazy(get_valid_filename, six.text_type)
 
+
 def get_text_list(list_, last_word=ugettext_lazy('or')):
     """
     >>> get_text_list(['a', 'b', 'c', 'd'])
@@ -245,10 +247,12 @@ def get_text_list(list_, last_word=ugettext_lazy('or')):
         force_text(last_word), force_text(list_[-1]))
 get_text_list = allow_lazy(get_text_list, six.text_type)
 
+
 def normalize_newlines(text):
     return force_text(re.sub(r'\r\n|\r|\n', '\n', text))
 normalize_newlines = allow_lazy(normalize_newlines, six.text_type)
 
+
 def recapitalize(text):
     "Recapitalizes text, placing caps after end-of-sentence punctuation."
     text = force_text(text).lower()
@@ -257,6 +261,7 @@ def recapitalize(text):
     return text
 recapitalize = allow_lazy(recapitalize)
 
+
 def phone2numeric(phone):
     "Converts a phone number with letters into its numeric equivalent."
     char2number = {'a': '2', 'b': '2', 'c': '2', 'd': '3', 'e': '3', 'f': '3',
@@ -267,6 +272,7 @@ def phone2numeric(phone):
     return ''.join(char2number.get(c, c) for c in phone.lower())
 phone2numeric = allow_lazy(phone2numeric)
 
+
 # From http://www.xhaus.com/alan/python/httpcomp.html#gzip
 # Used with permission.
 def compress_string(s):
@@ -276,6 +282,7 @@ def compress_string(s):
     zfile.close()
     return zbuf.getvalue()
 
+
 class StreamingBuffer(object):
     def __init__(self):
         self.vals = []
@@ -294,6 +301,7 @@ class StreamingBuffer(object):
     def close(self):
         return
 
+
 # Like compress_string, but for iterators of strings.
 def compress_sequence(sequence):
     buf = StreamingBuffer()
@@ -309,6 +317,7 @@ def compress_sequence(sequence):
 
 ustring_re = re.compile("([\u0080-\uffff])")
 
+
 def javascript_quote(s, quote_double_quotes=False):
 
     def fix(match):
@@ -340,6 +349,7 @@ smart_split_re = re.compile(r"""
     ) | \S+)
 """, re.VERBOSE)
 
+
 def smart_split(text):
     r"""
     Generator that splits a string by spaces, leaving quoted phrases together.
@@ -359,6 +369,7 @@ def smart_split(text):
     for bit in smart_split_re.finditer(text):
         yield bit.group(0)
 
+
 def _replace_entity(match):
     text = match.group(1)
     if text[0] == '#':
@@ -379,10 +390,12 @@ def _replace_entity(match):
 
 _entity_re = re.compile(r"&(#?[xX]?(?:[0-9a-fA-F]+|\w{1,8}));")
 
+
 def unescape_entities(text):
     return _entity_re.sub(_replace_entity, text)
 unescape_entities = allow_lazy(unescape_entities, six.text_type)
 
+
 def unescape_string_literal(s):
     r"""
     Convert quoted string literals to unquoted strings with escaped quotes and
@@ -403,6 +416,7 @@ def unescape_string_literal(s):
     return s[1:-1].replace(r'\%s' % quote, quote).replace(r'\\', '\\')
 unescape_string_literal = allow_lazy(unescape_string_literal)
 
+
 def slugify(value):
     """
     Converts to lowercase, removes non-word characters (alphanumerics and
diff --git a/django/utils/timesince.py b/django/utils/timesince.py
index 8fb0f64e09..b39ab203a7 100644
--- a/django/utils/timesince.py
+++ b/django/utils/timesince.py
@@ -6,6 +6,7 @@ from django.utils.html import avoid_wrapping
 from django.utils.timezone import is_aware, utc
 from django.utils.translation import ugettext, ungettext_lazy
 
+
 def timesince(d, now=None, reversed=False):
     """
     Takes two datetime objects and returns the time between d and now
@@ -56,6 +57,7 @@ def timesince(d, now=None, reversed=False):
             result += ugettext(', ') + avoid_wrapping(name2 % count2)
     return result
 
+
 def timeuntil(d, now=None):
     """
     Like timesince, but returns a string measuring the time until
diff --git a/django/utils/timezone.py b/django/utils/timezone.py
index 951c3efcf9..eec554a1ef 100644
--- a/django/utils/timezone.py
+++ b/django/utils/timezone.py
@@ -29,6 +29,7 @@ __all__ = [
 
 ZERO = timedelta(0)
 
+
 class UTC(tzinfo):
     """
     UTC implementation taken from Python's docs.
@@ -48,6 +49,7 @@ class UTC(tzinfo):
     def dst(self, dt):
         return ZERO
 
+
 class FixedOffset(tzinfo):
     """
     Fixed offset in minutes east from UTC. Taken from Python's docs.
@@ -72,6 +74,7 @@ class FixedOffset(tzinfo):
     def dst(self, dt):
         return ZERO
 
+
 class ReferenceLocalTimezone(tzinfo):
     """
     Local time. Taken from Python's docs.
@@ -118,6 +121,7 @@ class ReferenceLocalTimezone(tzinfo):
         tt = _time.localtime(stamp)
         return tt.tm_isdst > 0
 
+
 class LocalTimezone(ReferenceLocalTimezone):
     """
     Slightly improved local time implementation focusing on correctness.
@@ -143,6 +147,7 @@ class LocalTimezone(ReferenceLocalTimezone):
 utc = pytz.utc if pytz else UTC()
 """UTC time zone as a tzinfo instance."""
 
+
 def get_fixed_timezone(offset):
     """
     Returns a tzinfo instance with a fixed offset from UTC.
@@ -158,6 +163,7 @@ def get_fixed_timezone(offset):
 # wrap the expression in a function and cache the result.
 _localtime = None
 
+
 def get_default_timezone():
     """
     Returns the default time zone as a tzinfo instance.
@@ -173,6 +179,7 @@ def get_default_timezone():
             _localtime = LocalTimezone()
     return _localtime
 
+
 # This function exists for consistency with get_current_timezone_name
 def get_default_timezone_name():
     """
@@ -182,18 +189,21 @@ def get_default_timezone_name():
 
 _active = local()
 
+
 def get_current_timezone():
     """
     Returns the currently active time zone as a tzinfo instance.
     """
     return getattr(_active, "value", get_default_timezone())
 
+
 def get_current_timezone_name():
     """
     Returns the name of the currently active time zone.
     """
     return _get_timezone_name(get_current_timezone())
 
+
 def _get_timezone_name(timezone):
     """
     Returns the name of ``timezone``.
@@ -210,6 +220,7 @@ def _get_timezone_name(timezone):
 # These functions don't change os.environ['TZ'] and call time.tzset()
 # because it isn't thread safe.
 
+
 def activate(timezone):
     """
     Sets the time zone for the current thread.
@@ -224,6 +235,7 @@ def activate(timezone):
     else:
         raise ValueError("Invalid timezone: %r" % timezone)
 
+
 def deactivate():
     """
     Unsets the time zone for the current thread.
@@ -233,6 +245,7 @@ def deactivate():
     if hasattr(_active, "value"):
         del _active.value
 
+
 class override(object):
     """
     Temporarily set the time zone for the current thread.
@@ -297,6 +310,7 @@ def localtime(value, timezone=None):
         value = timezone.normalize(value)
     return value
 
+
 def now():
     """
     Returns an aware or naive datetime.datetime, depending on settings.USE_TZ.
@@ -307,6 +321,7 @@ def now():
     else:
         return datetime.now()
 
+
 # By design, these four functions don't perform any checks on their arguments.
 # The caller should ensure that they don't receive an invalid value like None.
 
@@ -319,6 +334,7 @@ def is_aware(value):
     """
     return value.tzinfo is not None and value.tzinfo.utcoffset(value) is not None
 
+
 def is_naive(value):
     """
     Determines if a given datetime.datetime is naive.
@@ -328,6 +344,7 @@ def is_naive(value):
     """
     return value.tzinfo is None or value.tzinfo.utcoffset(value) is None
 
+
 def make_aware(value, timezone):
     """
     Makes a naive datetime.datetime in a given time zone aware.
@@ -339,6 +356,7 @@ def make_aware(value, timezone):
         # may be wrong around DST changes
         return value.replace(tzinfo=timezone)
 
+
 def make_naive(value, timezone):
     """
     Makes an aware datetime.datetime naive in a given time zone.
diff --git a/django/utils/translation/__init__.py b/django/utils/translation/__init__.py
index d99c8bbd78..e4e8c6e1be 100644
--- a/django/utils/translation/__init__.py
+++ b/django/utils/translation/__init__.py
@@ -61,26 +61,33 @@ _trans = Trans()
 # The Trans class is no more needed, so remove it from the namespace.
 del Trans
 
+
 def gettext_noop(message):
     return _trans.gettext_noop(message)
 
 ugettext_noop = gettext_noop
 
+
 def gettext(message):
     return _trans.gettext(message)
 
+
 def ngettext(singular, plural, number):
     return _trans.ngettext(singular, plural, number)
 
+
 def ugettext(message):
     return _trans.ugettext(message)
 
+
 def ungettext(singular, plural, number):
     return _trans.ungettext(singular, plural, number)
 
+
 def pgettext(context, message):
     return _trans.pgettext(context, message)
 
+
 def npgettext(context, singular, plural, number):
     return _trans.npgettext(context, singular, plural, number)
 
@@ -88,6 +95,7 @@ gettext_lazy = lazy(gettext, str)
 ugettext_lazy = lazy(ugettext, six.text_type)
 pgettext_lazy = lazy(pgettext, six.text_type)
 
+
 def lazy_number(func, resultclass, number=None, **kwargs):
     if isinstance(number, int):
         kwargs['number'] = number
@@ -117,21 +125,27 @@ def lazy_number(func, resultclass, number=None, **kwargs):
         proxy = lazy(lambda **kwargs: NumberAwareString(), NumberAwareString)(**kwargs)
     return proxy
 
+
 def ngettext_lazy(singular, plural, number=None):
     return lazy_number(ngettext, str, singular=singular, plural=plural, number=number)
 
+
 def ungettext_lazy(singular, plural, number=None):
     return lazy_number(ungettext, six.text_type, singular=singular, plural=plural, number=number)
 
+
 def npgettext_lazy(context, singular, plural, number=None):
     return lazy_number(npgettext, six.text_type, context=context, singular=singular, plural=plural, number=number)
 
+
 def activate(language):
     return _trans.activate(language)
 
+
 def deactivate():
     return _trans.deactivate()
 
+
 class override(object):
     def __init__(self, language, deactivate=False):
         self.language = language
@@ -150,30 +164,39 @@ class override(object):
         else:
             activate(self.old_language)
 
+
 def get_language():
     return _trans.get_language()
 
+
 def get_language_bidi():
     return _trans.get_language_bidi()
 
+
 def check_for_language(lang_code):
     return _trans.check_for_language(lang_code)
 
+
 def to_locale(language):
     return _trans.to_locale(language)
 
+
 def get_language_from_request(request, check_path=False):
     return _trans.get_language_from_request(request, check_path)
 
+
 def get_language_from_path(path, supported=None):
     return _trans.get_language_from_path(path, supported=supported)
 
+
 def templatize(src, origin=None):
     return _trans.templatize(src, origin)
 
+
 def deactivate_all():
     return _trans.deactivate_all()
 
+
 def _string_concat(*strings):
     """
     Lazy variant of string concatenation, needed for translations that are
@@ -182,6 +205,7 @@ def _string_concat(*strings):
     return ''.join(force_text(s) for s in strings)
 string_concat = lazy(_string_concat, six.text_type)
 
+
 def get_language_info(lang_code):
     from django.conf.locale import LANG_INFO
     try:
diff --git a/django/utils/translation/trans_null.py b/django/utils/translation/trans_null.py
index 88c77a5110..9e3beb0f7d 100644
--- a/django/utils/translation/trans_null.py
+++ b/django/utils/translation/trans_null.py
@@ -6,18 +6,22 @@ from django.conf import settings
 from django.utils.encoding import force_text
 from django.utils.safestring import mark_safe, SafeData
 
+
 def ngettext(singular, plural, number):
     if number == 1:
         return singular
     return plural
 ngettext_lazy = ngettext
 
+
 def ungettext(singular, plural, number):
     return force_text(ngettext(singular, plural, number))
 
+
 def pgettext(context, message):
     return ugettext(message)
 
+
 def npgettext(context, singular, plural, number):
     return ungettext(singular, plural, number)
 
@@ -38,17 +42,20 @@ TECHNICAL_ID_MAP = {
     "MONTH_DAY_FORMAT": settings.MONTH_DAY_FORMAT,
 }
 
+
 def gettext(message):
     result = TECHNICAL_ID_MAP.get(message, message)
     if isinstance(message, SafeData):
         return mark_safe(result)
     return result
 
+
 def ugettext(message):
     return force_text(gettext(message))
 
 gettext_noop = gettext_lazy = _ = gettext
 
+
 def to_locale(language):
     p = language.find('-')
     if p >= 0:
@@ -56,8 +63,10 @@ def to_locale(language):
     else:
         return language.lower()
 
+
 def get_language_from_request(request, check_path=False):
     return settings.LANGUAGE_CODE
 
+
 def get_language_from_path(request, supported=None):
     return None
diff --git a/django/utils/translation/trans_real.py b/django/utils/translation/trans_real.py
index b79af80dd1..d78b6d6412 100644
--- a/django/utils/translation/trans_real.py
+++ b/django/utils/translation/trans_real.py
@@ -64,6 +64,7 @@ def to_locale(language, to_lower=False):
     else:
         return language.lower()
 
+
 def to_language(locale):
     """Turns a locale name (en_US) into a language name (en-us)."""
     p = locale.find('_')
@@ -72,6 +73,7 @@ def to_language(locale):
     else:
         return locale.lower()
 
+
 class DjangoTranslation(gettext_module.GNUTranslations):
     """
     This class sets up the GNUTranslations context with regard to output
@@ -98,6 +100,7 @@ class DjangoTranslation(gettext_module.GNUTranslations):
     def __repr__(self):
         return "<DjangoTranslation lang:%s>" % self.__language
 
+
 def translation(language):
     """
     Returns a translation object.
@@ -179,6 +182,7 @@ def translation(language):
 
     return current_translation
 
+
 def activate(language):
     """
     Fetches the translation object for a given tuple of application name and
@@ -187,6 +191,7 @@ def activate(language):
     """
     _active.value = translation(language)
 
+
 def deactivate():
     """
     Deinstalls the currently active translation object so that further _ calls
@@ -195,6 +200,7 @@ def deactivate():
     if hasattr(_active, "value"):
         del _active.value
 
+
 def deactivate_all():
     """
     Makes the active translation object a NullTranslations() instance. This is
@@ -203,6 +209,7 @@ def deactivate_all():
     """
     _active.value = gettext_module.NullTranslations()
 
+
 def get_language():
     """Returns the currently selected language."""
     t = getattr(_active, "value", None)
@@ -215,6 +222,7 @@ def get_language():
     from django.conf import settings
     return settings.LANGUAGE_CODE
 
+
 def get_language_bidi():
     """
     Returns selected language's BiDi layout.
@@ -227,6 +235,7 @@ def get_language_bidi():
     base_lang = get_language().split('-')[0]
     return base_lang in settings.LANGUAGES_BIDI
 
+
 def catalog():
     """
     Returns the current active catalog for further processing.
@@ -243,6 +252,7 @@ def catalog():
         _default = translation(settings.LANGUAGE_CODE)
     return _default
 
+
 def do_translate(message, translation_function):
     """
     Translates 'message' using the given 'translation_function' name -- which
@@ -266,6 +276,7 @@ def do_translate(message, translation_function):
         return mark_safe(result)
     return result
 
+
 def gettext(message):
     """
     Returns a string of the translation of the message.
@@ -280,6 +291,7 @@ else:
     def ugettext(message):
         return do_translate(message, 'ugettext')
 
+
 def pgettext(context, message):
     msg_with_ctxt = "%s%s%s" % (context, CONTEXT_SEPARATOR, message)
     result = ugettext(msg_with_ctxt)
@@ -288,6 +300,7 @@ def pgettext(context, message):
         result = message
     return result
 
+
 def gettext_noop(message):
     """
     Marks strings for translation but doesn't translate them now. This can be
@@ -297,6 +310,7 @@ def gettext_noop(message):
     """
     return message
 
+
 def do_ntranslate(singular, plural, number, translation_function):
     global _default
 
@@ -308,6 +322,7 @@ def do_ntranslate(singular, plural, number, translation_function):
         _default = translation(settings.LANGUAGE_CODE)
     return getattr(_default, translation_function)(singular, plural, number)
 
+
 def ngettext(singular, plural, number):
     """
     Returns a string of the translation of either the singular or plural,
@@ -327,6 +342,7 @@ else:
         """
         return do_ntranslate(singular, plural, number, 'ungettext')
 
+
 def npgettext(context, singular, plural, number):
     msgs_with_ctxt = ("%s%s%s" % (context, CONTEXT_SEPARATOR, singular),
                       "%s%s%s" % (context, CONTEXT_SEPARATOR, plural),
@@ -337,6 +353,7 @@ def npgettext(context, singular, plural, number):
         result = ungettext(singular, plural, number)
     return result
 
+
 def all_locale_paths():
     """
     Returns a list of paths to user-provides languages files.
@@ -346,6 +363,7 @@ def all_locale_paths():
         os.path.dirname(upath(sys.modules[settings.__module__].__file__)), 'locale')
     return [globalpath] + list(settings.LOCALE_PATHS)
 
+
 def check_for_language(lang_code):
     """
     Checks whether there is a global language file for the given language
@@ -359,6 +377,7 @@ def check_for_language(lang_code):
     return False
 check_for_language = memoize(check_for_language, _checked_languages, 1)
 
+
 def get_supported_language_variant(lang_code, supported=None, strict=False):
     """
     Returns the language-code that's listed in supported languages, possibly
@@ -386,6 +405,7 @@ def get_supported_language_variant(lang_code, supported=None, strict=False):
                     return supported_code
     raise LookupError(lang_code)
 
+
 def get_language_from_path(path, supported=None, strict=False):
     """
     Returns the language-code if there is a valid language-code
@@ -406,6 +426,7 @@ def get_language_from_path(path, supported=None, strict=False):
     except LookupError:
         return None
 
+
 def get_language_from_request(request, check_path=False):
     """
     Analyzes the request to find what language the user wants the system to
@@ -470,6 +491,8 @@ def get_language_from_request(request, check_path=False):
         return settings.LANGUAGE_CODE
 
 dot_re = re.compile(r'\S')
+
+
 def blankout(src, char):
     """
     Changes every non-whitespace character to the given char.
@@ -653,6 +676,7 @@ def templatize(src, origin=None):
                 out.write(blankout(t.contents, 'X'))
     return force_str(out.getvalue())
 
+
 def parse_accept_lang_header(lang_string):
     """
     Parses the lang_string, which is the body of an HTTP Accept-Language
diff --git a/django/views/debug.py b/django/views/debug.py
index 2829ca1443..0ee5d588c7 100644
--- a/django/views/debug.py
+++ b/django/views/debug.py
@@ -21,6 +21,7 @@ HIDDEN_SETTINGS = re.compile('API|TOKEN|KEY|SECRET|PASS|PROFANITIES_LIST|SIGNATU
 
 CLEANSED_SUBSTITUTE = '********************'
 
+
 def linebreak_iter(template_source):
     yield 0
     p = template_source.find('\n')
@@ -29,6 +30,7 @@ def linebreak_iter(template_source):
         p = template_source.find('\n', p+1)
     yield len(template_source) + 1
 
+
 def cleanse_setting(key, value):
     """Cleanse an individual setting key/value of sensitive content.
 
@@ -52,6 +54,7 @@ def cleanse_setting(key, value):
 
     return cleansed
 
+
 def get_safe_settings():
     "Returns a dictionary of the settings module, with sensitive settings blurred out."
     settings_dict = {}
@@ -60,6 +63,7 @@ def get_safe_settings():
             settings_dict[k] = cleanse_setting(k, getattr(settings, k))
     return settings_dict
 
+
 def technical_500_response(request, exc_type, exc_value, tb):
     """
     Create a technical server error response. The last three arguments are
@@ -76,6 +80,7 @@ def technical_500_response(request, exc_type, exc_value, tb):
 # Cache for the default exception reporter filter instance.
 default_exception_reporter_filter = None
 
+
 def get_exception_reporter_filter(request):
     global default_exception_reporter_filter
     if default_exception_reporter_filter is None:
@@ -87,6 +92,7 @@ def get_exception_reporter_filter(request):
     else:
         return default_exception_reporter_filter
 
+
 class ExceptionReporterFilter(object):
     """
     Base for all exception reporter filter classes. All overridable hooks
@@ -108,6 +114,7 @@ class ExceptionReporterFilter(object):
     def get_traceback_frame_variables(self, request, tb_frame):
         return list(six.iteritems(tb_frame.f_locals))
 
+
 class SafeExceptionReporterFilter(ExceptionReporterFilter):
     """
     Use annotations made by the sensitive_post_parameters and
@@ -221,6 +228,7 @@ class SafeExceptionReporterFilter(ExceptionReporterFilter):
 
         return cleansed.items()
 
+
 class ExceptionReporter(object):
     """
     A class to organize and coordinate reporting on exceptions.
@@ -491,6 +499,7 @@ def technical_404_response(request, exception):
     })
     return HttpResponseNotFound(t.render(c), content_type='text/html')
 
+
 def default_urlconf(request):
     "Create an empty URLconf 404 error response."
     t = Template(DEFAULT_URLCONF_TEMPLATE, name='Default URLconf template')
diff --git a/django/views/decorators/http.py b/django/views/decorators/http.py
index a0da002dc9..df4e165066 100644
--- a/django/views/decorators/http.py
+++ b/django/views/decorators/http.py
@@ -51,6 +51,7 @@ require_POST.__doc__ = "Decorator to require that a view only accept the POST me
 require_safe = require_http_methods(["GET", "HEAD"])
 require_safe.__doc__ = "Decorator to require that a view only accept safe methods: GET and HEAD."
 
+
 def condition(etag_func=None, last_modified_func=None):
     """
     Decorator to support conditional retrieval (or change) for a view
@@ -157,9 +158,11 @@ def condition(etag_func=None, last_modified_func=None):
         return inner
     return decorator
 
+
 # Shortcut decorators for common cases based on ETag or Last-Modified only
 def etag(etag_func):
     return condition(etag_func=etag_func)
 
+
 def last_modified(last_modified_func):
     return condition(last_modified_func=last_modified_func)
diff --git a/django/views/decorators/vary.py b/django/views/decorators/vary.py
index cd2f9c0f55..056669278b 100644
--- a/django/views/decorators/vary.py
+++ b/django/views/decorators/vary.py
@@ -2,6 +2,7 @@ from functools import wraps
 from django.utils.cache import patch_vary_headers
 from django.utils.decorators import available_attrs
 
+
 def vary_on_headers(*headers):
     """
     A view decorator that adds the specified headers to the Vary header of the
@@ -22,6 +23,7 @@ def vary_on_headers(*headers):
         return inner_func
     return decorator
 
+
 def vary_on_cookie(func):
     """
     A view decorator that adds "Cookie" to the Vary header of a response. This
diff --git a/django/views/generic/dates.py b/django/views/generic/dates.py
index 370cb32ce7..d221c2c087 100644
--- a/django/views/generic/dates.py
+++ b/django/views/generic/dates.py
@@ -13,6 +13,7 @@ from django.views.generic.base import View
 from django.views.generic.detail import BaseDetailView, SingleObjectTemplateResponseMixin
 from django.views.generic.list import MultipleObjectMixin, MultipleObjectTemplateResponseMixin
 
+
 class YearMixin(object):
     """
     Mixin for views manipulating year-based data.
diff --git a/django/views/i18n.py b/django/views/i18n.py
index 9ede1ed49f..751905efaf 100644
--- a/django/views/i18n.py
+++ b/django/views/i18n.py
@@ -13,6 +13,7 @@ from django.utils._os import upath
 from django.utils.http import is_safe_url
 from django.utils import six
 
+
 def set_language(request):
     """
     Redirect to a given url while setting the chosen language in the
diff --git a/django/views/static.py b/django/views/static.py
index e55f6a1234..11c8734eec 100644
--- a/django/views/static.py
+++ b/django/views/static.py
@@ -17,6 +17,7 @@ from django.utils.http import http_date, parse_http_date
 from django.utils.six.moves.urllib.parse import unquote
 from django.utils.translation import ugettext as _, ugettext_noop
 
+
 def serve(request, path, document_root=None, show_indexes=False):
     """
     Serve static files below a given point in the directory structure.
@@ -95,6 +96,7 @@ DEFAULT_DIRECTORY_INDEX_TEMPLATE = """
 """
 template_translatable = ugettext_noop("Index of %(directory)s")
 
+
 def directory_index(path, fullpath):
     try:
         t = loader.select_template(['static/directory_index.html',
@@ -113,6 +115,7 @@ def directory_index(path, fullpath):
     })
     return HttpResponse(t.render(c))
 
+
 def was_modified_since(header=None, mtime=0, size=0):
     """
     Was something modified since the user last downloaded it?