Fixed #11353 -- `GeometryProxy` descriptor no longer chokes when accessed from a class rather than an instance, thanks yml and Tobu; removed unnecessary imports from `types` and cleaned up whitespace.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@12584 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/contrib/gis/db/models/proxy.py

@@ -1,13 +1,11 @@
 """
- The GeometryProxy object, allows for lazy-geometries.  The proxy uses
- Python descriptors for instantiating and setting Geometry objects
- corresponding to geographic model fields.
+The GeometryProxy object, allows for lazy-geometries.  The proxy uses
+Python descriptors for instantiating and setting Geometry objects
+corresponding to geographic model fields.
 
- Thanks to Robert Coup for providing this functionality (see #4322).
+Thanks to Robert Coup for providing this functionality (see #4322).
 """
 
-from types import NoneType, StringType, UnicodeType
-
 class GeometryProxy(object):
     def __init__(self, klass, field):
         """
@@ -23,6 +21,10 @@ class GeometryProxy(object):
         class specified during initialization and the HEXEWKB value of the field.
         Currently, only GEOS or OGR geometries are supported.
         """
+        if obj is None:
+            # Accessed on a class, not an instance
+            return self
+
         # Getting the value of the field.
         geom_value = obj.__dict__[self._field.attname]
 
@@ -51,8 +53,8 @@ class GeometryProxy(object):
         if isinstance(value, self._klass) and (str(value.geom_type).upper() == gtype or gtype == 'GEOMETRY'):
             # Assigning the SRID to the geometry.
             if value.srid is None: value.srid = self._field.srid
-        elif isinstance(value, (NoneType, StringType, UnicodeType)):
-            # Set with None, WKT, or HEX
+        elif value is None or isinstance(value, (basestring, buffer)):
+            # Set with None, WKT, HEX, or WKB
             pass
         else:
             raise TypeError('cannot set %s GeometryProxy with value of type: %s' % (obj.__class__.__name__, type(value)))