I'm running Linux-Lite 4.2 the shell is bash.
I need to make a macro, or perhaps its called a script, to allow me to enter "python3.7 app.py" into terminal when I press a key combination.

I tried installing a program called autokey. I tried installing it several different ways but I keep getting errors when trying to run it.

I can't find any other program that inserts a line of pre-written text when pressing a key combination. I can't put the line of text in clipboard and paste because I am already doing that constantly for another part of this process (hard to explain).
Point is, since I only need to insert this text into bash, is there a way bash can be setup to perform this macro?

Otherwise does anyone know of an alternative to autokey?

well if you got to press keys then try using an alias in your .bashrc
or whatever ...

thank you, I never knew about this thing called alias. I did alias a='python3.7 app.py' so I just hit a and enter. It's one of those super repetitive tasks where I am doing this over and over for hours (again, it's hard to explain what I am actually doing). and when i close terminal the alias disappears (which is good, I only need the alias for this one task). I'll look into modifying the .bashrc if I ever need to make a perma alias. Anyhow, thank you, how do I mark this post as solved?

if you just add that to your .bashrc file which ever terminal you open it is there at your disposal.
marked solved in the top of your post there is a link saying marked solved.