Mark: fix python 3 compatibility

_pytest/compat.py

@@ -111,7 +111,7 @@ if  sys.version_info[:2] == (2, 6):
 
 if _PY3:
     import codecs
-
+    imap = map
     STRING_TYPES = bytes, str
 
     def _escape_strings(val):
@@ -145,6 +145,8 @@ if _PY3:
 else:
     STRING_TYPES = bytes, str, unicode
 
+    from itertools import imap
+
     def _escape_strings(val):
         """In py2 bytes and str are the same type, so return if it's a bytes
         object, return it unchanged if it is a full ascii string,
@@ -213,4 +215,4 @@ def _is_unittest_unexpected_success_a_failure():
         Changed in version 3.4: Returns False if there were any
         unexpectedSuccesses from tests marked with the expectedFailure() decorator.
     """
-    return sys.version_info >= (3, 4)
+    return sys.version_info >= (3, 4)

_pytest/mark.py

@@ -2,7 +2,7 @@
 import inspect
 from collections import namedtuple
 from operator import attrgetter
-from itertools import imap
+from .compat import imap
 
 def alias(name):
     return property(attrgetter(name), doc='alias for ' + name)