Python references

Anh-Thi Dinh

For checking

Google, of course!

programiz.com

Python Reference on iOS.

Courses

Python 3 tutorial on TutorialsPoint.

Python Tutorial on W3School.

Python Tutorials by Corey Schafer on Youtube.

Python 3 on Codecademy (paid).

Python fundamentals on PluralSight (paid).

Jobtensor's docs.

Practice

Hackerrank.

Exercism.

CodeSignal.

CodeChef.

Others

Newsletter for python news.

Time complexity (Big O) of various operators in CPython.