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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 serialize_m2m_on_save(sender, action, instance, using, **kwargs):
 """ Part of the serialize transaction process that ensures m2m are serialized correctly. Skip those not registered. """

    if action == "post_add":
        try:
            wrapped_instance = site_offline_models.get_wrapped_instance(instance)
        except ModelNotRegistered:
            pass
        else:
            wrapped_instance.to_outgoing_transaction(using, created=True)