This is a port of the excellent python module named the same, which can be found here appdirs (now deprecated and replaced by platformdirs).
The original port was written by wessie this is a maintained fork of that project.
When writing desktop application, finding the right location to store user data and configuration varies per platform. Even for single-platform apps, there may by plenty of nuances in figuring out the right location.
For example, if running on macOS, you should use
~/Library/Application Support/<AppName>
If on Windows (at least English Win) that should be::
C:\Documents and Settings\<User>\Application Data\Local Settings\<AppAuthor>\<AppName>
or possibly::
C:\Documents and Settings\<User>\Application Data\<AppAuthor>\<AppName>
for roaming profiles but that is another story.
On Linux (and other Unices), according to the XDG Basedir Spec, it should be
~/.local/share/<AppName>
This library provides a simple to use API to get the appropriate storage directories no matter the platform and what you want to store.