Add a way to run python 3 without having to change run options every time

I've been researching it for a while. Every time every few months that I want to run python 3 I end up googling and scrolling through the same pages. But over the time I've always had this issues with script. Could you please make it easier.
Now every time I have to run python 3 I have to press cmd-shift-i and type python3 for "command" option.
I would like to be able to just press cmd-i and get my code running. I'm sure I'm not the only one who would like that