What is the difference between quit() and exit(), sys.exit() in python?

Question

They seem to do the same thing. What is the difference between quit(), sys.exit() and exit() in python?

Answer 1

https://stackoverflow.com/questions/19747371/JUMP_LINK__&&__python__&&__JUMP_LINK-exit-commands-why-so-many-and-when-should-each-be-used