func (*DefaultTime) AfterFunc(d time.Duration, f func()) Timer {
	return time.AfterFunc(d, f)
}
func (*DefaultTime) AfterFunc(d time.Duration, f func()) Timer {
	return time.AfterFunc(d, f)
}
// AfterFunc waits for the duration to elapse and then calls f in its own
// goroutine. It returns a Timer that can be used to cancel the call using its
// Stop method.