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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 post_save_event_listener(sender, instance, created):
 """Event listener to create creation and update events."""

    if not instance._meta.event_ready:
        return

    if created:
        instance.create_creation_event()
    else:
        instance.create_update_event()

    # Reset the original key
    instance._original = None