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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 find_interface_by_mac(self, **kwargs):
 """Find the interface through which a MAC can be reached. Args: mac_address (str):
 A MAC address in 'xx:xx:xx:xx:xx:xx' format. Returns: list[dict]: a list of mac table data. Raises: KeyError: if `mac_address` is not specified. Examples: """

        mac = kwargs.pop('mac_address')
        results = [x for x in self.mac_table if x['mac_address'] == mac]
        return results