Avijit Dutta enhanced code quality in the sympy/sympy repository by introducing explicit type annotations to the smoothness function within the ntheory.factor_.py module. Using Python and leveraging type hinting, Avijit clarified the function’s input and output contracts by specifying a SupportsIndex parameter and a tuple of integers as the return type. This targeted update improved static type safety and maintainability, aligning the codebase with modern Python development practices. While the work focused on a single feature and did not address bug fixes, it contributed to cleaner interfaces and facilitated easier onboarding for future contributors maintaining or extending the code.