def main():
    ''' Run the client. '''
    try:
        host = sys.argv[1]
        port = int(sys.argv[2])
    except (IndexError, ValueError):
        print('Usage: {} <HOST> <PORT>'.format(sys.argv[0]))
        sys.exit(1)

    try:
        wsproto_demo(host, port)
    except KeyboardInterrupt:
        print('\nReceived SIGINT: shutting down…')