what is None,True,False in python?

Question

Are they keywords, constants, or functions? If they are constants, what are their types? It seems python has no type of boolean.

`None` is of type `NoneType`. `True` and `False` are of type `bool`. You can type `type(True)` or for any variable on the REPL to figure out its type — sshashank124, May 16 '18 at 05:39
“It seems python has no type of boolean.” Eh? `bool`? Anyway, they’re keywords that act as constants/literals, because Python doesn’t have that kind of constant. (In Python 2, only `None` is a keyword, and you can actually assign values to `True` and `False`.) — Ry-, May 16 '18 at 05:39
I dont understand why this question received so many downvotes. — Bedir Yilmaz, May 16 '18 at 05:42
Not that I downvoted, but it very easily google-able stuff as it's been asked/answered in many different places — sshashank124, May 16 '18 at 05:44
Possible duplicate of [False or None vs. None or False](https://stackoverflow.com/questions/3914667/false-or-none-vs-none-or-false) — akshat, May 16 '18 at 05:52
Open a shell and type `bool`. It comes back as ``. So python does have a boolean type. — tdelaney, May 16 '18 at 06:08
This is now the top answer on google for "Is None True in Python", so I think it could use a link to a canonical answer — Fr4nc3sc0NL, Jun 05 '20 at 18:27
I didn't understand why this question has gotten negative feedback, I think some are quick to judge and punish. — Vivek Shukla, Jun 09 '20 at 13:57

score 3 · Answer 1 · edited Jun 20 '20 at 09:12

The Python Documentation has it all, one just has to know where to look:

https://docs.python.org/3/library/constants.html

A small number of constants live in the built-in namespace. They are:

False

The false value of the bool type. Assignments to False are illegal and raise a SyntaxError.

True

The true value of the bool type. Assignments to True are illegal and raise a SyntaxError.

None

The sole value of the type NoneType. None is frequently used to represent the absence of a value, as when default arguments are not passed to a function. Assignments to None are illegal and raise a SyntaxError.

Also

None

This type has a single value. There is a single object with this value. This object is accessed through the built-in name None. It is used to signify the absence of a value in many situations, e.g., it is returned from functions that don’t explicitly return anything. Its truth value is false.

and

Booleans (bool)

These represent the truth values False and True. The two objects representing the values False and True are the only Boolean objects. The Boolean type is a subtype of the integer type, and Boolean values behave like the values 0 and 1, respectively, in almost all contexts, the exception being that when converted to a string, the strings "False" or "True" are returned, respectively.

what is None,True,False in python?

1 Answers1