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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 get_form(self, request, rel, admin_site):
 """Return filter form."""

        return DynamicRawIDFilterForm(
            admin_site=admin_site,
            rel=rel,
            field_name=self.field_path,
            data=self.used_parameters,
        )