code: def feed(self, can):
          
          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:])
docs: Attempt to feed an incoming CAN frame into the state machine