def METHOD_NAME(self, client):
    input_ap_str = PetAPString(
        id = 3,
        name = 'Tommy',
        additional_properties = {
            'color': 'red',
            'weight': '10 kg',
            'city': 'Bombay'
        }
    )
    output_ap_str = client.pets.create_ap_string(input_ap_str)
    assert output_ap_str.additional_properties['color'] ==  'red'