Contributed to the leanprover-community/mathlib4 repository by enhancing the topology library with new eq'' variants for infinite product and sum lemmas, focusing on proof symmetry and maintainability. Leveraging expertise in Lean, formal verification, and mathematics, the work mirrored existing eq' patterns to align with Piecewise and Finsupp modules, enabling more straightforward proofs for indicator-function summability. The implementation included updating tactics to use convert! for improved reliability. These changes improved cross-module consistency and proof ergonomics, particularly supporting Polya-lean usage. The contribution centered on feature development, with no separate bug fixes, and demonstrated depth in formal mathematical library engineering.