def METHOD_NAME(create_empty_data):
    """
    Returns an echo server that calls the function `create_empty_data(nbytes)`
    to create the data container.`
    """
    async def echo_server(ep):
        """
        Basic echo server for sized messages.
        We expect the other endpoint to follow the pattern::
        # size of the real message (in bytes)
        >>> await ep.send(msg_size)
        >>> await ep.send(msg)       # send the real message
        >>> await ep.recv(responds)  # receive the echo
        """
        msg_size = np.empty(1, dtype=np.uint64)
        await ep.recv(msg_size)
        msg = create_empty_data(msg_size[0])
        await ep.recv(msg)
        await ep.send(msg)
        await ep.close()
    return echo_server