Run and handle external application from python

I want to develop Python script that will open some windows-based application, then enter some data/commands simulating user using keyboard:

• Run MS Calculator then: "5", "+", "8", "/", "2", "Enter" and that's it
• Run MS Notepad then: "Hello world!", "Ctrl+s", "My file", "Enter", "Alt+F4"

Of course it could return exiting code like 1 when succeed and write some logs.

I believe there is some library (probably for UI testing purpouses) but I don't know any.

I know there is Selenium but I'm afraid it's only for web browser app.