Python Return Values

Satellite · Functions

Python Return Values

Functions are powerful when they communicate clearly. Learn how to return structured data, multiple values, and handle the implicit None.

Return tuplesAdd type hints

Basics

def total(items: list[float]) -> float:
    return sum(items)

• If no return executes, the function returns None.
• Early returns improve readability by exiting when conditions fail.

Multiple values

def min_max(values: list[int]) -> tuple[int, int]:
    return min(values), max(values)

low, high = min_max(scores)

Python packs return values into tuples automatically.

Structured returns

• Use dataclasses or TypedDicts for richer payloads.
• For optional data, return Optional[T] (e.g., -> Optional[str]).

Type hints

from typing import Optional

def find_user(id: str) -> Optional[dict]:
    ...

Documenting return types helps IDEs and static analyzers catch misuse.

Next up in your learning path

Combine with *args/**kwargs

Design flexible function signatures end-to-end.

Companion

Adopt dataclasses

Return structured records instead of tuples.

Advanced

Document behavior with tests

Write unit tests asserting expected return values.

Practice