How to Check for Not None in Python Programming

Like we have NUL, NULL, or null in other programming languages, in Python we have None which is used to represent the absence of a value.

In order to check if a particular object is None or not, we can make use of the If condition as below,

Syntax 1:

if variable is not None:

Syntax 2:

def function(object):
    if object is not None:
        # Your code Logic
    else:
        # Your code Logic

It is always better to look at the PEP (Python Enhancement Proposals) Guides to know what they say.

As per PEP-8

# Correct:
if foo is not None:

# Wrong:
if not foo is None:

Read More: Programming Recommendations

Now let's take a look at a few examples.

def check_for_none(object):
    if object is not None:
        print(f"The object is: {object}")
    else:
        print("The object is None!")

check_for_none(42)
check_for_none("Hello")
check_for_none(None)

Output:

The object is: 42
The object is: Hello
The object is None!