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

[NArshad]

-Whose time??  
My time
I do not have not time to switch to a database but if necessary I can use the database to make changes in Excel column entries. 

-No changes??

I cannot change the column names.


-“maybe the point is that at any time one has to be able to re-export to the original excel format?  (And why??  Do we actually need "reporting": then we can generate a PDF rather, otherwise we can just send out a CSV... etc.)  Is that it?”

PDF is not required and I am not doing any reporting at all. 


-“loading the data from the CSV file in memory into a pandas dataframe, working with that, and eventually saving back to the CSV file might be just enough... as long as there is never more than one user concurrently using the system, or you need also implement some concurrency management (you need that with a database, too, anyway): but that's tutorial number 2, and already quite less trivial, since to begin with it requires a more thorough analysis”

No need to save the CSV file once the work is done CSV file will be exited without saving. If the above is going to work then I will be requiring something to see how to do all this that’s why written tutorial. For a more thorough analysis I have written once again what I want to do. 

Only the four functions that I have written below I have to make and that’s it. All the input will be entered by the user on a website:
1. First, I have to check in the Excel sheet or table whether the book user has entered is present in the book bank or not.
 
2. If a book is present and the quantity of the required book is greater than 0 (COPIES_LEFT column in excel file) and if the user wants the book, it will be assigned to the user which he will take from the book bank physically. When COPIES_LEFT is less than or equal to 0 the message will be “Book finished or not present”.
 
3. The quantity of the book in the Excel file will be reduced by 1 in the COPIES_LEFT column and the name of the borrower or user will be entered/added in the Excel file table or sheet already made and the column name is BORROWER’S NAME.
 
4. The borrower’s or user name can be more than one so they will be separated with a comma in the Excel file BORROWER’S NAME column.


-1st save the data from excel as a CSV file

you will find the CSV module makes these much easier to deal with, even if
you do not import into a DB (although even then I would import into SQL-
lite just for the benefits of the search algorithms)

If in order to do the required task it is necessary to use SQLite and without using SQLite I cannot do what I want to do then I think I have to go for SQLite otherwise CSV looks to me as fine. To do everything using CSV I will be requiring a tutorial to see how to do all this. 

Anything not clear?