You can just read columns and rows in CSVs though and import them all into a data structure (probably a dictionary for what you're after - of type {key,value} ={address, balance} or = {address, list[balance,txs,etc]).
Exactly!
I could make two csv files and just compare them with WinMerge. Then I can get duplicates on both sides and get private keys for that list.
I am using Linux also.