Schedule a new event. The time argument should be a numeric type
compatible with the return value of the timefunc function passed
to the constructor. Events scheduled for
the same time will be executed in the order of their
priority.
Executing the event means executing
action(*argument). argument must be a
sequence holding the parameters for action.
Return value is an event which may be used for later cancellation of
the event (see cancel()).
enter(
delay, priority, action, argument)
Schedule an event for delay more time units. Other then the
relative time, the other arguments, the effect and the return value
are the same as those for enterabs().
cancel(
event)
Remove the event from the queue. If event is not an event
currently in the queue, this method will raise a
RuntimeError.
empty(
)
Return true if the event queue is empty.
run(
)
Run all scheduled events. This function will wait
(using the delayfunc function passed to the constructor)
for the next event, then execute it and so on until there are no more
scheduled events.
Either action or delayfunc can raise an exception. In
either case, the scheduler will maintain a consistent state and
propagate the exception. If an exception is raised by action,
the event will not be attempted in future calls to run().
If a sequence of events takes longer to run than the time available
before the next event, the scheduler will simply fall behind. No
events will be dropped; the calling code is responsible for canceling
events which are no longer pertinent.