          kwargs['null'] = True
          Field.__init__(self, *args, **kwargs)
  
      def to_python(self, value):
          if value in (None, True, False): return value
          if value in ('None'): return None
          if value in ('t', 'True', '1'): return True
 
</s>
    def get_internal_type(self):
        return "NullBooleanField"

          kwargs['null'] = True
          Field.__init__(self, *args, **kwargs)
  
    def get_internal_type(self):
        return "NullBooleanField"

      def to_python(self, value):
          if value in (None, True, False): return value
          if value in ('None'): return None
          if value in ('t', 'True', '1'): return True
keep keep add keep keep keep keep
 It makes sense that when you subclass an existing model field, you're often
going to be using the same database column type. Made that properly
inheritable (previously it was using the class name), at the cost of a little
more verboseness.

This is very slightly backwards incompatible (for subclasses of existing fields
that were relying on the old default).

Fixed #6556.


git-svn-id: http://code.djangoproject.com/svn/django/trunk@7133 bcc190cf-cafb-0310-a4f2-bffc1f526a37
django/db/models/fields/__init__.py