Python function return nothing

There is no such thing as “returning nothing” in the Python function. If no explicit return statement is used, Python treats it as returning None.

def f(x):
    if x>1:
       return(x)
    else:
        # don't return anything

To return ‘nothing’ use pass, which returns the value None if put in a function(Functions must return a value, so why not ‘nothing’). You can do this explicitly and return None yourself though.

Python function returns nothing

Simple example code.

def f(x):
    if x > 1:
        return x
    else:
        pass


print(f(0))

or

def f(x):
    if x > 1:
        return x
    else:
        print("Function Return literally nothing")
        None


print(f(0))

Output:

Python Function Return None Without Return Statement

The function does not have a return statement. The function in that case implicitly returns None.

def func():
    pass


print(func())

Output: None

Here’s an example showing different scenarios where a function might return None:

def example_function_1():
    pass  # No return statement

def example_function_2():
    return None  # Explicitly returns None

def example_function_3(condition):
    if condition:
        return "Condition met"
    # No return statement if condition is False

def example_function_4(value):
    if value > 10:
        return "Greater than 10"
    # No return statement if value is 10 or less

result1 = example_function_1()  # result1 will be None
result2 = example_function_2()  # result2 will be None
result3 = example_function_3(False)  # result3 will be None
result4 = example_function_4(5)  # result4 will be None

print(result1)  # Output: None
print(result2)  # Output: None
print(result3)  # Output: None
print(result4)  # Output: None

In each of these examples, the functions return None for different reasons.

Comment if you have any doubts or suggestions on this Python return topic.

Note: IDE: PyCharm 2021.3.3 (Community Edition)

Windows 10

Python 3.10.1

All Python Examples are in Python 3, so Maybe its different from python 2 or upgraded versions.