Added type annotations, thanks so much to awordforthat for the contribution!
To use in CircuitPython, simply install the [Adafruit CircuitPython Bundle](https://circuitpython.org/libraries).
To use in CPython, `pip3 install adafruit-circuitpython-ble-berrymed-pulse-oximeter`.
Read the [docs](http://circuitpython.readthedocs.io/projects/ble-berrymed-pulse-oximeter/en/latest/) for info on how to use it.