What approaches or tools help ensure code readability and maintainability?

To ensure readability and maintainability of code in Python, several approaches and tools are used:

• Clean and clear coding style: following PEP 8 — the official Python coding style.
• Naming: using meaningful and descriptive names for variables, functions, and classes.
• Documentation: writing docstrings for functions and classes to explain their purpose and parameters.
• Modularity: breaking down code into small functions and modules, each responsible for a single task.
• Type annotations: type hints help understand what data is expected and returned.
• Testing: writing automated tests to verify code correctness.
• Static analysis tools: such as pylint, flake8, mypy for style and type checking.

Example of a simple Python function with a docstring and annotations:

from typing import List

def sum_positive_numbers(numbers: List[int]) -> int:
    """Returns the sum of positive numbers in the list."""
    return sum(n for n in numbers if n > 0)