The None in Python keyword is used to define a null variable or an object. It can be assigned to any variable, but you cannot create other None types of objects. The none type in Python is an object and it belongs to the class NoneType.
In Python, none defines NULL values and there are two kinds of none: True None and False None.
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None in Python: A Singular Entity
All variables that are assigned None point to the same object. New instances of None are not created.
This means that if you assign one variable with the value of None, and then reassign it to another variable with a different value, both variables will still hold the same reference to the same object in memory – so changes made on either side will also be reflected on the other side.
This is very different from most languages, where assignment to a variable creates a new instance of that object in memory. This means there are many copies of the None object created and manipulated throughout your program’s execution time – which can be wasteful if you don’t need them all!
None is a keyword in Python, which can be used as both an identifier and as a literal value. None supports the use of either ‘is’ or ‘==’ operators to test for its existence. It also has two syntaxes, one using just the keyword None and another that encloses it within parenthesis (None).
Example 01: Using ‘is’ Operator
var = None if var is None: print("None Value") else: print("Not None Value")
Example 02: Using ‘==’ Operator
var = None if var == None: print("None Value") else: print("Not None Value")
Example 03: Check type of None
var = type(None) print(var)
Example 04: Comparison of None with None, False, String
print(None == None) print(None == False) print(None == str)
None in Python is an object and it belongs to the class NoneType. If you want to assign NULL values or create objects of type none, then do so by assigning them with a value of “None” like this: x = None. There are two kinds of none that can be used in python – True False.