python-project-structure

Python project structure relies on grouping related code into cohesive modules and defining explicit public APIs using `__all__`. Establishing a consistent directory hierarchy from the outset ensures maintainability and prevents future refactoring headaches.

The best way to define a public API in a Python module is by using the `__all__` variable. This explicitly declares which functions and classes are part of the public interface, ensuring discoverability and hiding internal implementation details.

Test file placement in a Python project depends on your directory layout patterns. This skill provides guidance on conventional test file placement alongside flat or nested directory structures to ensure codebase discoverability and clear module architecture.

You need a nested directory hierarchy for larger Python codebases requiring strict module architecture, while a flat structure suits simpler projects. This skill provides patterns for both to ensure file cohesion and scalable code organization.

You can use this guidance to refactor an existing Python codebase by applying its module architecture conventions. Reorganizing files for better module cohesion and defining explicit interfaces improves codebase navigation and maintainability.