You can run this on pre-commit. While you can set PyCharm to run on file save, it is not guaranteed to run on all files. By using a command line tool, you can enforce that all files across your project are formatted this specific way and never let someone check in something that doesn't conform to it. If you have newbie developers, it can be a lifesaver.

You edit code, test it, and then have some program rewrite your code after testing but before it becomes an immutable commit hash?

Why do you want your code formatter tied explicitly to an IDE? Why would you want to force everyone on your team to use the same editor?

Use independent components, and let people use what they work best in.

You’re acting as if it’s inconceivable that there are people that don’t use PyCharm out there....

Not everyone runs PyCharm, and this tool is open source.

PyCharm itself is open source.

https://github.com/JetBrains/intellij-community/tree/master/...

I'm also assuming pycharm has some options. This thing seems to make very specific decisions and if you don't agree with them, tough.