SOSD | A Benchmark for Learned Indexes | Performance Testing library

I have a script that loops through multiple years of data, one year at a time. Each year of data consists of multiple dataframes that are placed in a list called all_input. At the beginning of the loop (after the data is read in), I am trying to get all of the years of data in the same format before the rest of the processing.

The issue I am having is with column names, which are not uniform. There are 5 columns included in each dataframe that I want to keep, and I want them to be called total_emissions uom tribal_name st_usps_cd and description. In some dataframes they already have these names, while in others they have various names such as pollutant.desc or pollutant_desc, for example.

My current approach is this: