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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_port_if_removed(self, port):
 """Enqueue port delete"""

        instance_type = self.get_instance_type(port)
        if not instance_type:
            return
        port_type = instance_type + a_const.PORT_SUFFIX
        if not db_lib.port_provisioned(port['id']):
            p_res = MechResource(port['id'], port_type, a_const.DELETE)
            self.provision_queue.put(p_res)