Remove the need for six

[mcepl]

If you ever decide that Python 2 is truly dead and rotting in its grave, you may apply this patch removing the need of using six at all.

[gruns]

💯 this; py2 is absolutely dead and rotting in the grave 🪦️️

I'm about to drop py2 testing support. py2 is longgggg past EOL

@mcepl ill take a look at your patch removing six. ty! 🙏