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The Null Object in Python

Python does not have a null object. But the most closely related similar object is none. In this article, we will see how how None behaves in Python.

Checking the type of Null and None we see that there is no Null Type and the None object is of type NoneType.

Example

print(type(None))
print(type(Null))

Output

Running the above code gives us the following result −

Traceback (most recent call last):
   File "C:\Users\xxx\scratch.py", line 4, in
      print(type(Null))
NameError: name 'Null' is not defined

Key facts about None

  • None is the same as False.

  • None is the same as False.

  • None is the same as False.

  • None is an empty string.

  • None is 0.

  • Comparing None to anything will always return False except None itself.

Null Variables in Python

An undefined variable is not the same as a Null variable. A variable will be null in Python if you assign None to it.

Example

var_a = None
print('var_a is: ',var_a)
print(var_b)

Output

Running the above code gives us the following result −

Traceback (most recent call last):
   File "C:\Users\Pradeep\AppData\Roaming\JetBrains\PyCharmCE2020.3\scratches\scratch.py", line 5, in <module>
      print(var_b)
NameError: name 'var_b' is not defined
var_a is: None

None not associated with methods

If something is declared as None, you can not use any methods to add, remove elements from it.

Example

listA = [5,9,3,7]
listA.append(18)
print(listA)
listA = None
listA.append(34)
print(listA)

Output

Running the above code gives us the following result −

[5, 9, 3, 7, 18]
Traceback (most recent call last):
   File "C:\Users\Pradeep\AppData\Roaming\JetBrains\PyCharmCE2020.3\scratches\scratch.py", line 7, in
      listA.append(34)
AttributeError: 'NoneType' object has no attribute 'append'