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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 loop(self, timeout=1.0, max_packets=1):
 """Process network events. This function must be called regularly to ensure communication with the broker is carried out. It calls select() on the network socket to wait for network events. If incoming data is present it will then be processed. Outgoing commands, from e.g. publish(), are normally sent immediately that their function is called, but this is not always possible. loop() will also attempt to send any remaining outgoing messages, which also includes commands that are part of the flow for messages with QoS>0. timeout: The time in seconds to wait for incoming/outgoing network traffic before timing out and returning. max_packets: Not currently used. Returns MQTT_ERR_SUCCESS on success. Returns >0 on error. A ValueError will be raised if timeout < 0"""

        if timeout < 0.0:
            raise ValueError('Invalid timeout.')

        self._current_out_packet_mutex.acquire()
        self._out_packet_mutex.acquire()
        if self._current_out_packet is None and len(self._out_packet) > 0:
            self._current_out_packet = self._out_packet.pop(0)

        if self._current_out_packet:
            wlist = [self.socket()]
        else:
            wlist = []
        self._out_packet_mutex.release()
        self._current_out_packet_mutex.release()

        # sockpairR is used to break out of select() before the timeout, on a
        # call to publish() etc.
        rlist = [self.socket(), self._sockpairR]
        try:
            socklist = select.select(rlist, wlist, [], timeout)
        except TypeError as e:
            # Socket isn't correct type, in likelihood connection is lost
            return MQTT_ERR_CONN_LOST
        except ValueError:
            # Can occur if we just reconnected but rlist/wlist contain a -1 for
            # some reason.
            return MQTT_ERR_CONN_LOST
        except:
            return MQTT_ERR_UNKNOWN

        if self.socket() in socklist[0]:
            rc = self.loop_read(max_packets)
            if rc or (self._ssl is None and self._sock is None):
                return rc

        if self._sockpairR in socklist[0]:
            # Stimulate output write even though we didn't ask for it, because
            # at that point the publish or other command wasn't present.
            socklist[1].insert(0, self.socket())
            # Clear sockpairR - only ever a single byte written.
            try:
                self._sockpairR.recv(1)
            except socket.error as err:
                if err.errno != EAGAIN:
                    raise

        if self.socket() in socklist[1]:
            rc = self.loop_write(max_packets)
            if rc or (self._ssl is None and self._sock is None):
                return rc

        return self.loop_misc()