def METHOD_NAME(self, m):
    mock_service_oas_get(m, "https://catalogus.nl/api/v1/", "catalogi")
    m.get(
        "https://catalogus.nl/api/v1/roltypen?zaaktype=https://catalogus.nl/api/v1/zaaktypen/111",
        status_code=200,
        json={
            "count": 0,
            "next": None,
            "previous": None,
            "results": [],
        },
    )
    data = {
        "zgw_api_group": self.zgw_group.pk,
        "zaaktype": "https://catalogus.nl/api/v1/zaaktypen/111",
        "medewerker_roltype": "Some description",
    }
    serializer = ZaakOptionsSerializer(data=data)
    is_valid = serializer.is_valid()
    self.assertFalse(is_valid)
    self.assertIn("non_field_errors", serializer.errors)
    self.assertEqual(
        "Could not find a roltype with this description related to the zaaktype",
        serializer.errors["non_field_errors"][0],
    )