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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_for_dbfield(self, db_field, **kwargs):
 """ Make slug mandatory. """

        if db_field.name == "slug":
            kwargs["required"] = True
            kwargs["help_text"] = None
        return super(LinkAdmin, self).formfield_for_dbfield(db_field, **kwargs)