Return values

Getting results from functions

So far, our functions have printed output. But often you want functions to calculate something and give you the result to use elsewhere.

# This function only prints
def add_print(a, b):
    print(a + b)

# This function returns a value
def add_return(a, b):
    return a + b

# Now you can use the result
result = add_return(5, 3)
print(f"The result is {result}")  # The result is 8

The return statement

Use return to send a value back from a function:

def calculate_area(width, height):
    area = width * height
    return area

# Store the returned value
room_area = calculate_area(10, 12)
print(f"Room size: {room_area} sq ft")  # Room size: 120 sq ft

When Python hits a return statement, it immediately exits the function. Any code after return won’t run.

Using returned values

Returned values can be used in many ways:

def double(number):
    return number * 2

# Store in variable
result = double(5)

# Use in expressions
total = double(5) + double(3)  # 10 + 6 = 16

# Pass to other functions
print(double(10))  # 20

# Use in conditions
if double(7) > 10:
    print("Big number!")

Returning multiple values

Python can return multiple values as a tuple:

def get_min_max(numbers):
    return min(numbers), max(numbers)

# Get both values
minimum, maximum = get_min_max([5, 2, 8, 1, 9])
print(f"Min: {minimum}, Max: {maximum}")  # Min: 1, Max: 9

# Or as a tuple
result = get_min_max([5, 2, 8, 1, 9])
print(result)  # (1, 9)

Return vs print

Understanding the difference is crucial:

def get_greeting_print(name):
    print(f"Hello, {name}!")  # Just displays

def get_greeting_return(name):
    return f"Hello, {name}!"  # Gives back value

# Can't use print version's output
message = get_greeting_print("Alice")  # Prints but returns None
print(message)  # None

# Can use return version's output
message = get_greeting_return("Alice")  # Returns the string
print(message.upper())  # HELLO, ALICE!

Use return when you need to use the result elsewhere. Use print when you just want to display information.

Functions without return

Functions without explicit return statements return None:

def greet(name):
    print(f"Hello, {name}!")
    # No return statement

result = greet("Alice")  # Prints: Hello, Alice!
print(result)  # None

Common mistakes

Forgetting to return

# Wrong - calculates but doesn't return
def calculate_total(items):
    total = sum(items)
    # Forgot return!

# Right
def calculate_total(items):
    total = sum(items)
    return total

Code after return

# Wrong - code after return never runs
def get_status():
    return "Done"
    print("This never prints!")  # Unreachable

# Right - return last
def get_status():
    print("Checking status...")
    return "Done"

Printing instead of returning

# Wrong - prints instead of returning
def multiply(a, b):
    print(a * b)

result = multiply(3, 4)  # Prints 12
total = result + 10      # Error! result is None

# Right - return the value
def multiply(a, b):
    return a * b

What’s next?

Now that you know the basics of functions, let’s look at how to handle arguments flexibly using variable-length and special parameters.

Flexible Argument Handling

Master *args, **kwargs, positional-only, and keyword-only parameters

Functions

Classes

Error handling

Modules & Packages

Extending Python

Getting results from functions

The return statement

Using returned values

Returning multiple values

Return vs print

Functions without return

Common mistakes

What’s next?

Flexible Argument Handling

​Getting results from functions

​The return statement

​Using returned values

​Returning multiple values

​Return vs print

​Functions without return

​Common mistakes

​What’s next?

Flexible Argument Handling

Getting results from functions

The return statement

Using returned values

Returning multiple values

Return vs print

Functions without return

Common mistakes

What’s next?