def METHOD_NAME(self, app):
    resp = app.get(
        "http://localhost/service?SERVICE=WMS&REQUEST=GetMap"
        "&LAYERS=direct&STYLES="
        "&WIDTH=100&HEIGHT=100&FORMAT=image/png"
        "&BBOX=-10000,0,0,1000&SRS=EPSG:25832"
        "&VERSION=1.1.0&TRANSPARENT=TRUE"
    )
    # empty/transparent response
    assert resp.content_type == "image/png"
    assert is_png(resp.body)
    assert is_transparent(resp.body)