Upgrade deprecated github setup-python action to v4.
tree719b8f41df48966431b8f08570c6fe14f6679945
-rw-r--r-- 1494 .appveyor.yml
drwxr-xr-x - .appveyor
drwxr-xr-x - .circleci
drwxr-xr-x - .github
-rw-r--r-- 242 .gitignore
-rw-r--r-- 1419 CONTRIBUTING.md
-rw-r--r-- 35147 COPYING
-rw-r--r-- 141 MANIFEST.in
-rw-r--r-- 7529 README.md
drwxr-xr-x - bin
-rw-r--r-- 6024 makefile
drwxr-xr-x - po
-rw-r--r-- 454 setup.cfg
-rw-r--r-- 7398 setup.py
drwxr-xr-x - share
drwxr-xr-x - src
drwxr-xr-x - tests
drwxr-xr-x - tools