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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 delete_tenant_if_removed(self, tenant_id):
 """Enqueue tenant delete if it's no longer in the db"""

        if not db_lib.tenant_provisioned(tenant_id):
            t_res = MechResource(tenant_id, a_const.TENANT_RESOURCE,
                                 a_const.DELETE)
            self.provision_queue.put(t_res)