<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def on_play_speed(self, *args):
 """Change the interval at which ``self.play`` is called to match my current ``play_speed``. """

        Clock.unschedule(self.play)
        Clock.schedule_interval(self.play, 1.0 / self.play_speed)