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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 uplink_bond_intf_process(self):
 """Process the case when uplink interface becomes part of a bond. This is called to check if the phy interface became a part of the bond. If the below condition is True, this means, a physical interface that was not a part of a bond was earlier discovered as uplink and now that interface became part of the bond. Usually, this doesn't happen as LLDP and in turn this function will first detect a 'down' followed by an 'up'. When regular interface becomes part of bond, it's rare for it to hit this 'normal' case. But, still providing the functionality if it happens. The following is done : a. Bring down the physical interface by sending a 'down' event b. Add the bond interface by sending an 'up' event Consquently, when bond is added that will be assigned to self.phy_uplink. Then, the below condition will be False. i.e.. 'get_bond_intf' will return False, when the argument is 'bond0'. """

        bond_intf = sys_utils.get_bond_intf(self.phy_uplink)
        if bond_intf is None:
            return False
        self.save_uplink(
            fail_reason=constants.port_transition_bond_down_reason)
        self.process_uplink_ongoing = True
        upl_msg = VdpQueMsg(constants.UPLINK_MSG_TYPE, status='down',
                            phy_uplink=self.phy_uplink,
                            br_int=self.br_integ, br_ex=self.br_ex,
                            root_helper=self.root_helper)
        self.que.enqueue(constants.Q_UPL_PRIO, upl_msg)
        self.phy_uplink = None
        self.veth_intf = None
        self.uplink_det_compl = False

        # No veth interface
        self.save_uplink(
            uplink=bond_intf,
            fail_reason=constants.port_transition_bond_up_reason)
        self.phy_uplink = bond_intf
        self.process_uplink_ongoing = True
        upl_msg = VdpQueMsg(constants.UPLINK_MSG_TYPE, status='up',
                            phy_uplink=self.phy_uplink,
                            br_int=self.br_integ, br_ex=self.br_ex,
                            root_helper=self.root_helper)
        self.que.enqueue(constants.Q_UPL_PRIO, upl_msg)
        return True