I don't understand how to find if a key is being pressed if the parameter is a integer.
I am trying to use the [key definition list](https://github.com/kitao/pyxel/blob/master/pyxel/__init__.py) to get if a key is being pressed because I was referred there by the wiki. However, everything on the file that I need to use (lines 83-219) are all strings, but Pyxel needs a integer to see if a key is being pressed. So how do I actually know what integer I need?