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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 get(self, interface_id):
 """ Obtain routing configuration for a specific interface by ID. .. note:: If interface is a VLAN, you must use a str to specify the interface id, such as '3.13' (interface 3, VLAN 13) :param str,int interface_id: interface identifier :raises InterfaceNotFound: invalid interface for engine :return: Routing element, or None if not found :rtype: Routing """

        for interface in self:
            if interface.nicid == str(interface_id) or \
                interface.dynamic_nicid == str(interface_id):
                return interface
        raise InterfaceNotFound('Specified interface {} does not exist on '
            'this engine.'.format(interface_id))