def release(self, conn):
        """
        Release a connection back to the pool.

        :param gremlinclient.connection.Connection: The connection to be
            released
        """
        future = self._future_class()
        if self.maxsize <= self.size:
            if conn.closed:
                # conn has been closed
                pool_logger.info(
                    "Released closed connection: {}".format(conn))
                self._acquired.remove(conn)
                conn = None
            elif self._waiters:
                waiter = self._waiters.popleft()
                waiter.set_result(conn)
                pool_logger.debug(
                    "Completeing future with connection: {}".format(conn))
            else:
                self._pool.append(conn)
                self._acquired.remove(conn)
            future.set_result(None)
        else:
            future_conn = conn.close()
            future_conn.add_done_callback(
                lambda f: future.set_result(f.result()))
        return future
dataset/ETHPy150Open davebshow/gremlinclient/gremlinclient/pool.py/Pool.release/swapped operands of `<=`