Can I have same functionality as re.findall() without using any module directly in python?

Question

My task is to use automata theory for autocorrect text. All my references show the use of re.findall() for the purpose of finding matches. Can I recreate the functionality without using any library directly. I am allowed to use different function form different libraries.

I am expecting something like source code for findall() function.

Answer 1

CPython is open source. The sourcecode for the re package is on github.