How to Create Find and Replace Function for Google Drive File Names with Google Scripts

Basically, I have a bunch of files in a shared google drive, let's say:

AA123_1.jpg
AA123_2.jpg
AA123_3.jpg
...

I am trying to get rid of all of the "123"'s and replace them with an empty space, or just replace "123_" with "_". I am not particularly familiar with google scripts (I do understand basic programming logic though), but yeah, basically I was wondering if anyone knows how I could make a script for this as there is a very large amount of files. Thanks ever so much.