how to open a library and read its contents

this might be a stupid question, im kinda new to python, and programming in general.

the thing is i want to see how a library was coded, so i can imitate it and learn. but everything i find is how to import libraries. i don't want to just install a library and use it blindly. i want to be able to recreate it.

is there any way to open a library and see how is it coded?