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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def migrateDown(self):
 """ Remove the components in the site store for this SubScheduler. """

        subStore = self.store.parent.getItemByID(self.store.idInParent)
        ssph = self.store.parent.findUnique(
            _SubSchedulerParentHook,
            _SubSchedulerParentHook.subStore == subStore,
            default=None)
        if ssph is not None:
            te = self.store.parent.findUnique(TimedEvent,
                                              TimedEvent.runnable == ssph,
                                              default=None)
            if te is not None:
                te.deleteFromStore()
            ssph.deleteFromStore()