How to use the ogame.constants.Defense.keys function in ogame

def get_code(name):
    if name in constants.Buildings.keys():
        return constants.Buildings[name]
    if name in constants.Facilities.keys():
        return constants.Facilities[name]
    if name in constants.Defense.keys():
        return constants.Defense[name]
    if name in constants.Ships.keys():
        return constants.Ships[name]
    if name in constants.Research.keys():
        return constants.Research[name]
    print('Couldn\'t find code for {}'.format(name))
    return None