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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 feed(self, can):
 """Attempt to feed an incoming CAN frame into the state machine"""

        if not isinstance(can, CAN):
            raise Scapy_Exception("argument is not a CAN frame")
        identifier = can.identifier
        data = bytes(can.data)

        if len(data) > 1 and self.use_ext_addr is not True:
            self._try_feed(identifier, None, data)
        if len(data) > 2 and self.use_ext_addr is not False:
            ea = six.indexbytes(data, 0)
            self._try_feed(identifier, ea, data[1:])