Worked on the optuna/optuna repository to enhance the maintainability and readability of the test suite, specifically focusing on the test_study.py file. Applied code refactoring techniques using Python, replacing legacy .format() calls with modern f-strings to improve code clarity and reduce formatting errors. Addressed indentation and formatting inconsistencies throughout the test suite, which streamlines onboarding for new contributors and reduces test brittleness. Incorporated additional assertions to verify optimization and trial states, strengthening test reliability. All changes were delivered as a single, traceable patch, minimizing risk to production code while ensuring long-term maintainability and consistency within the testing framework.