def METHOD_NAME(self, size):
    """
    We have received a certain number of bytes from the remote peer. This
    necessarily shrinks the flow control window!
    :param size: The number of flow controlled bytes we received from the
        remote peer.
    :type size: ``int``
    :returns: Nothing.
    :rtype: ``None``
    """
    self.current_window_size -= size
    if self.current_window_size < 0:
        raise FlowControlError("Flow control window shrunk below 0")