If you have experience with other programming languages, like C or Java, then you’ve probably heard of the concept of
null. Many languages use this to represent a pointer that doesn’t point to anything, to denote when a variable is empty, or to mark default parameters that you haven’t yet supplied.
null is often defined to be
0 in those languages, but
null in Python is different.
Python uses the keyword
None to define
null objects and variables. While
None does serve some of the same purposes as
null in other languages, it’s another beast entirely. As the
null in Python,
None is not defined to be
0 or any other value. In Python,
None is an object and a first-class citizen!
In this course, you’ll learn:
Noneis and how to test for it
- When and why to use
Noneas a default parameter
NoneTypemean in your traceback
- How to use
Nonein type checking
nullin Python works under the hood