Added missing form argument in modelform_factory() docstring.
@@ -476,7 +476,9 @@ def modelform_factory(model, form=ModelForm, fields=None, exclude=None,
labels=None, help_texts=None, error_messages=None,
field_classes=None):
"""
- Return a ModelForm containing form fields for the given model.
+ Return a ModelForm containing form fields for the given model. You can
+ optionally pass a `form` argument to use as a starting point for
+ constructing the ModelForm.
``fields`` is an optional list of field names. If provided, include only
the named fields in the returned fields. If omitted or '__all__', use all
