find_free_port.py

def find_free_port(candidates=[]):
    for p in (candidates + [0]):
        with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
            try:
                s.bind(('localhost',p))
                return s.getsockname()[1]
            except Exception:
                logging.info(f"Could not bind to port {p}. Trying another")

port = find_free_port([5001,5010,5100])
print(f"Free port: {port}")