compare_patch

$ python late_patch.py
sleep(seconds)

Delay execution for a given number of seconds.  The argument may be
a floating point number for subsecond precision.
$ python eager_patch.py

    Put the current greenlet to sleep for at least *seconds*.

    *seconds* may be specified as an integer, or a float if fractional
    seconds are desired.

    .. tip:: In the current implementation, a value of 0 (the default)
       means to yield execution to any other runnable greenlets, but
       this greenlet may be scheduled again before the event loop
       cycles (in an extreme case, a greenlet that repeatedly sleeps
       with 0 can prevent greenlets that are ready to do I/O from
       being scheduled for some (small) period of time); a value greater than
       0, on the other hand, will delay running this greenlet until
       the next iteration of the loop.

    If *ref* is False, the greenlet running ``sleep()`` will not prevent :func:`gevent.wait`
    from exiting.

    .. seealso:: :func:`idle`