schedule a greenlet to be stopped immediately

    :param target: the greenlet to end
    :type target: greenlet

def end(target):
    """schedule a greenlet to be stopped immediately

    :param target: the greenlet to end
    :type target: greenlet
    """
    if not isinstance(target, compat.greenlet):
        raise TypeError("argument must be a greenlet")
    if not target.dead:
        schedule(target)
        state.to_raise[target] = compat.GreenletExit()