Python: How to make random characters and numbers appear all over the screen, from up to down like an animation?

as the title says. How do i make random characters and numbers appear all over the screen perfectly, from up to down like an animation. With details, it should start with the first ever line (not necessarily a line, it can be byte by byte) in the console's window, fill it up with random characters and numbers, delay the screen probably with milliseconds because it's an animation and pass to the other line repeating the same process until it reaches the last line of the console, in Python. I tried to look it up since i don't know how to do it and came up with no results at all, I want it for a program I'm making to give it some nice loading screen or so.

-Thanks and have a great day!