Make examples compatible with both 8.x.x and 9.0.0

The example code with `import fourwire` shows up on this guide:
https://learn.adafruit.com/adafruit-2-9-eink-display-breakouts-and-featherwings/circuitpython-usage

So the guide is using only 9.0.0-compatible code. The example(s) should be reworked to be compatible with both, at least for now.

There are probably other libraries where this happened.

Start with the CircuitPython usage guide linked in the issue and locate the example that imports `fourwire`. Check the example against both CircuitPython 8.x.x and 9.0.0; done means the example works with both versions. The issue also mentions other potentially affected libraries, but does not identify them.

Written by the indexing model from the issue text.