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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 save_entity_signal_handler(sender, instance, **kwargs):
 """ Defines a signal handler for saving an entity. Syncs the entity to the entity mirror table. """

    if instance.__class__ in entity_registry.entity_registry:
        sync_entities(instance)

    if instance.__class__ in entity_registry.entity_watching:
        sync_entities_watching(instance)