Merge pull request #359 from nmartini/ticket_18832

   to exclude from the form.

For example, if you want a form for the ``Author`` model (defined

above) that includes only the ``name`` and ``title`` fields, you would

above) that includes only the ``name`` and ``birth_date`` fields, you would

specify ``fields`` or ``exclude`` like this::

    class PartialAuthorForm(ModelForm):

        class Meta:

            model = Author

            fields = ('name', 'title')

            fields = ('name', 'birth_date')

    class PartialAuthorForm(ModelForm):

        class Meta:

            model = Author

            exclude = ('birth_date',)

            exclude = ('title',)

Since the Author model has only 3 fields, 'name', 'title', and

'birth_date', the forms above will contain exactly the same fields.