The standard library for Python offers a variety of ready to use tools for data work. Python comes with full functionality to read and write excel, cvs, json, and a variety of other formats that data comes in. In particular Python's pathlib, regex, and logging modules offer great tools for anyone working with data
Pandas is perhaps THE library for data manipulation and analysis. Getting good at Pandas is almost synonymous with becoming a proficient data operator. Pandas is simple to use but difficult to truly master.