pytype

Automatically infers types in unannotated code, reducing the need for explicit annotations, as highlighted in its key features for gradual typing.

Analyzes Python bytecode to perform type checking at a deeper level, providing insights beyond surface annotations for catching complex errors.

Works with interface files and inline annotations, making it ideal for migrating existing codebases to typed code with minimal disruption.

Collaborated on typeshed with Guido and mypy, demonstrating its reliability and historical impact on the Python typing community.