def METHOD_NAME(client, monkeypatch, agency_data, helpers):
    helpers.mock_current_fiscal_year(monkeypatch)
    resp = client.get(URL.format(code="001", filter=""))
    assert resp.status_code == status.HTTP_200_OK
    assert resp.data["fiscal_year"] == helpers.get_mocked_current_fiscal_year()
    assert resp.data["toptier_code"] == "001"
    assert resp.data["abbreviation"] == "ABBR"
    assert resp.data["name"] == "NAME"
    assert resp.data["agency_id"] == 1
    assert resp.data["mission"] == "TO BOLDLY GO"
    assert resp.data["about_agency_data"] == "ABOUT"
    assert resp.data["website"] == "HTTP"
    assert resp.data["congressional_justification_url"] == "BECAUSE"
    assert resp.data["icon_filename"] == "HAI.jpg"
    assert resp.data["subtier_agency_count"] == 1
    assert resp.data["def_codes"] == [
        {"code": "L", "public_law": "LAW", "title": "title", "urls": None, "disaster": "covid_19"}
    ]
    assert resp.data["messages"] == []
    resp = client.get(URL.format(code="001", filter=f"?fiscal_year={helpers.get_mocked_current_fiscal_year()}"))
    assert resp.status_code == status.HTTP_200_OK
    assert resp.data["fiscal_year"] == helpers.get_mocked_current_fiscal_year()
    assert resp.data["toptier_code"] == "001"
    assert resp.data["subtier_agency_count"] == 1
    resp = client.get(URL.format(code="001", filter=f"?fiscal_year={helpers.get_mocked_current_fiscal_year() - 1}"))
    assert resp.status_code == status.HTTP_200_OK
    assert resp.data["fiscal_year"] == helpers.get_mocked_current_fiscal_year() - 1
    assert resp.data["toptier_code"] == "001"
    assert resp.data["subtier_agency_count"] == 1
    resp = client.get(URL.format(code="002", filter=""))
    assert resp.status_code == status.HTTP_200_OK
    assert resp.data["fiscal_year"] == helpers.get_mocked_current_fiscal_year()
    assert resp.data["toptier_code"] == "002"
    assert resp.data["agency_id"] == 2
    assert resp.data["subtier_agency_count"] == 0