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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 read(self):
 """We have been called to read! As a consumer, continue to read for the length of the packet and then pass to the callback. """


        data = self.dev.read()

        if len(data) == 0:
            self.log.warning("READ : Nothing received")
            return

        if data == b'\x00':
            self.log.warning("READ : Empty packet (Got \\x00)")
            return

        pkt = bytearray(data)
        data = self.dev.read(pkt[0])
        pkt.extend(bytearray(data))

        self.log.info("READ : %s" % self.format_packet(pkt))
        self.do_callback(pkt)
        return pkt