AI engineering glossary · Python core
What is none?
None: The single built-in value that represents the absence of a meaningful value. It is the only instance of type NoneType and is what a function returns when it has no return statement. Test for it with the is operator, not ==.
None: an example
def greet(): print('hi') returns None, so result = greet() sets result to None. Use if result is None: to check it.
Related terms
More Python core terms
Where you learn it
None is part of the AI Engineering Program, which teaches it with notes, a hands-on lab and an exam. The first lesson is free.