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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 _fill_topology_cfg(self, topo_dict):
 """Fills the extra configurations in the topology. """

        cfg_dict = {}
        if topo_dict.bond_member_ports is not None:
            cfg_dict.update({'bond_member_ports':
                             topo_dict.bond_member_ports})
        if topo_dict.bond_interface is not None:
            cfg_dict.update({'bond_interface':
                             topo_dict.bond_interface})
        return cfg_dict