python 3.10 compatibility #109

Hey,

is there anything that stops the library to be officially marked as Python 3.10 compatible? 🤔 setup.py is configured with all 3 py versions up to "Programming Language :: Python :: 3.9" - is it deliberate that python 3.10 is missing ?

This package is reported as incompatible with Python 3.10 on this site https://pyreadiness.org/3.10/ that lists packages compatible with py3.10 based on Programming Language :: Python :: 3.10 classifier.

Please update the classifiers if there's no issue with Python 3.10.