Migrated the field_subclsasing doctests. Thanks to Alex Gaynor.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@13780 bcc190cf-cafb-0310-a4f2-bffc1f526a37

tests/modeltests/field_subclassing/fields.py

@@ -53,18 +53,18 @@ class SmallField(models.Field):
 
 class JSONField(models.TextField):
     __metaclass__ = models.SubfieldBase
-    
+
     description = ("JSONField automatically serializes and desializes values to "
         "and from JSON.")
-    
+
     def to_python(self, value):
         if not value:
             return None
-        
+
         if isinstance(value, basestring):
             value = json.loads(value)
         return value
-    
+
     def get_db_prep_save(self, value):
         if value is None:
             return None