Along with micropython-hmac (MicroPython doesn't include hmac), and the touch sensor on an ESP32 I threw together an authenticator with the same inspiration as this project. It seems to work quite well, overall.
micropython-lib packages aren't included in the base MicroPython (well, not the main one. The Pycopy fork does), and are published on PyPI under micropython-x. You've found the source for the package I named.
