Introduction to None in Python
A null variable or object is define with the None keyword. The None keyword is an object in Python, and it is a data type of the NoneType class.
None can be assigned to any variable, but noneType objects cannot be created.
Note: All variables that are assigned None point to the same object. New instances of None are not created.
Syntax: The syntax of the None statement is:
Note: None statement supports both is and == operators.
- It is not the same as False.
- None is not 0.
- Comparing None to anything will always return False except None itself.
- None is not an empty string.
Example 01: Checking if a variable is None using is operator:
# Declaring a None variable var = None if var is None: # Checking if the variable is None print("None") else: print("Not None")
Example 02: Checking if a variable is None using == operator:
# Declaring a None variable var = None if var == None: # Checking if the variable is None print("None") else: print("Not None")
Example 03: Check the type of
# Declaring a variable and initializing with None type typeOfNone = type(None) print(typeOfNone)
Example 04: Comparing
# Comparing None with none and printing the result print (None == None)
Example 05: Comparing
# Comparing none with False and printing the result print(None == False)
Example 06: Comparing
None with empty
# Declaring an empty string str = "" # Comparing None with empty string and printing the result print (str == None)
Is None a keyword in Python?
The term None is use in Python to specify null objects and variables. While None serves some of the same functions as null in other languages, it’s a whole different beast. None is not specified to be 0 or any other value in Python because it is the null value. None is an object and a first-class citizen in Python!
Is None and null the same?
None implies nothing, and nothing is a term that expresses the absence of all things. Nothing and Null are frequently mistaken, although they are completely different ideas. Nothing denotes the lack of anything, whereas Null denotes the unknown (you do not know if there is a thing or not).
Are None and 0 the same in Python?
None is not specified to be 0 or any other value in Python because it is the null value. None is an object and a first-class citizen in Python!