Worked on enhancing the pandas-dev/pandas-stubs repository by implementing keyword-argument support for the Styler.apply_index and Styler.map_index methods. This update allowed arbitrary keyword arguments to be passed to functions used in Styler operations, improving flexibility and aligning the API more closely with pandas’ core Styler functionality. The work involved updating Python type stubs, adding comprehensive tests to validate the new behavior, and ensuring that the changes addressed a usability gap for downstream projects. Leveraged skills in Python, data analysis, and testing to deliver a feature that streamlines DataFrame styling and reduces the need for workaround code in user projects.