The message queue method now returns `None` if no messages are in the queue, instead of returning `-1`.
To use in CircuitPython, simply install the [Adafruit CircuitPython bundle](https://github.com/adafruit/Adafruit_CircuitPython_Bundle).
Read the [docs](https://circuitpython.readthedocs.io/projects/azureiot/en/latest/) for info on how to use it.