I was trying to install PyUserInput on os x El Capitan, but I couldn't manage to do so. In the git repository instructions it is written that Quartz and AppKit are needed, but I can't figure out how to install them.
I would appreciate your help, Thanks!
Welcome to Stack Overflow.
Whenever you have to install dependencies, you should look into the package manager for the programming language (or operating system). In your case, the package manager for Python is pip.
You can use the package managers through your shell (command prompt, terminal, etc.)
Quartz. You can find the documentation here
pip install -U pyobjc
AppKit. You can find the documentation here
pip install appkit
Then, you can install PyUserInput. The repo for PyUserInput is here.