code: def set_client_key(self, zmq_socket, client_secret_key_path, server_public_key_path):
          '''must call before bind'''
          load_and_set_key(zmq_socket, client_secret_key_path)
          server_public, _ = zmq.auth.load_certificate(server_public_key_path)
          zmq_socket.curve_serverkey = server_publif set_client_key(self, zmq_socket, client_secret_key_path, server_public_key_path):
          '''must call before bind'''
          load_and_set_key(zmq_socket, client_secret_key_path)
          server_public, _ = zmq.auth.load_certificate(server_public_key_path)
          zmq_socket.curve_serverkey = server_public
docs: must call before bind