Libraries in Python?

Question

Which Python 3 libraries should one learn first? What are their applications?

Answer 1

learn the default library first, since it comes with every python install. it can accomplish most basic stuff

Answer 2

A library contains fuctions that handle the complicate stuff for you. you should learn the one you need.
I often use pySerial because my purpose is to handle serial comunication with external peripherals. Your purpose may be different so there is no priority except personal preference and need.