def METHOD_NAME(self):
    """
    Add a zaak with an external zaaktype
    """
    zaak_add_url = reverse("admin:zaken_zaak_add")
    response = self.app.get(zaak_add_url)
    form = response.form
    form["_zaaktype_base_url"] = self.service.pk
    form["_zaaktype_relative_url"] = "zaken/c10edbb4-d038-4333-a9ba-bbccfc8fa8bd"
    form["vertrouwelijkheidaanduiding"] = VertrouwelijkheidsAanduiding.openbaar
    form["bronorganisatie"] = "517439943"
    form["verantwoordelijke_organisatie"] = "517439943"
    form["startdatum"] = "2023-01-01"
    form["registratiedatum"] = "2023-01-01"
    submit_response = form.submit()
    self.assertEqual(submit_response.status_code, 302)