What are the best practices for using mypy?

What are the best practices for using mypy in my Python projects?

Some best practices for using mypy include: 1) Use type hints consistently, 2) Gradually add type checking to your codebase, 3) Use mypy.ini for configuration, and 4) Regularly run mypy as part of your CI/CD pipeline.

How can I gradually add type hints to an existing codebase?

Start by adding type hints to the most critical parts of your code, such as public APIs and functions that are frequently used. You can also use the --ignore-missing-imports flag to help mypy focus on your code without getting overwhelmed by third-party libraries.

What should I do if mypy reports a lot of errors?

Focus on fixing the most critical errors first. You can also use the --follow-imports option to control how mypy checks imported modules. Additionally, consider using type comments for complex types to simplify the process.

Can I use mypy with third-party libraries?

Yes, you can use mypy with third-party libraries. Many popular libraries provide type stubs, or you can create your own stubs if they don't. You can also use the --ignore-missing-imports flag to bypass errors from libraries without type hints.