message: increase readability
diff: @@ -174,7 +174,8 @@ def discover_channels(path, serial_number, callback, cancellation_token, printer
  continue
  else:
  printer("USB device init failed. Ignoring this device")
  + known_devices.append((usb_device.bus, usb_device.address))
  else:
  - callback(channel)
  known_devices.append((usb_device.bus, usb_device.address))
  + callback(channel)
  time.sleep(1)
  