What to write or search on github to get the code for what is written below:

[Avi Gross]

I am not replying to anything below so I have removed it.
So I need to remind people of the topic and how it has wandered.
Someone has data in a not particularly great format in an EXCEL spreadsheet. They want to somehow use an external language like Python to manipulate the contents from outside and keep the results inside the same or perhaps another EXCEL file.
Now EXCEL has had programming available for a long time within the spreadsheet and perhaps some of that was once used within the actual spreadsheet and stored as macros or whatever using something like VBA. Or perhaps someone used to update by hand.
So the suggestions to copy the data ONCE into something else (a CSV, database, whatever) that can be used externally are reasonable but seem to be resisted. I would guess some of the "missing" functionality others wonder about such as making reports, may still be available within other sheets or parts of the EXCEL .xlsx or other format file.
An interesting third option that has not been mentioned would be to port the data into another application like Google Sheets which has a fairly similar spreadsheet format with very different internals but many ways for a program to read and adjust the contents such as Google Apps Script that can also do things like send out emails and so on.
Instead, someone suggested Python which indeed, with lots of work, can open just about ANY nonsensical file and diddle around and rewrite it, but WHY? Unless you find the right modules and use them carefully, it seems the hard way to go. Sure, you can in theory do it but the amount of learning and work involved seems excessive  for what you get. And when you are done with what was requested here, you probably need to add other features that will again be painful. If you were hiring someone with experience, you might be paying more and more and end up with a package hard for anyone else to understand, let alone maintain and expand.
An intermediate solution seems to be to copy the darn data from EXCEL and modifies it to be easy to use and make changes  but make available functionality that saves the data when needed back into an EXCEL file, but most of the time manipulates it the easy way. 
As such, if the request continues to be to do it the hard way, i may be among those who ignores this thread any further.