def METHOD_NAME(self, request, *args, **kwargs):
    if "file_content" not in request.session:
        return HttpResponseRedirect(
            reverse(
                "admin:catalogi_catalogus_import_zaaktype",
                kwargs={"catalogus_pk": kwargs["catalogus_pk"]},
            )
        )
    return super().METHOD_NAME(request, *args, **kwargs)