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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def formfield(self, **kwargs):
 """ Provide the custom form widget for the admin, since there isn't a form field mapped to ``GenericRelation`` model fields. """

        from yacms.generic.forms import KeywordsWidget
        kwargs["widget"] = KeywordsWidget
        return super(KeywordsField, self).formfield(**kwargs)