Csv is already built into python. Don't use pandas unless you have a specific reason to. Especially if you're new to python. Also, you should use Google before posting questions. "Python csv" obviously informs you of the built in csv library and lots of examples https://docs.python.org/3/library/csv.html More on reddit.com

Looks interesting, following your RSS feed to see where what you'll come up with! More on reddit.com

https://docs.python.org/3/library/csv.html is where I'd start. More on reddit.com

You need to attack this problem by breaking it into smaller chunks.

First you need to break your encoded machine name string into the relevant parts.

So "epdmolpd37901v" -> ("e", "pd", "molpd", ...)

Write a single function to do this. Note that with Python you can return multiple values from a single function. Test it independently.

I'll assume that the translations.csv file does not have many millions of rows. You can use the csv module to read the whole file into memory and create a dictionary where

translations = {
    "P": "Production", 
    "E": "External User Acceptance",
    ...
    }

Again, write a function which reads this file and returns a dict as above and test this independently.

Next you need to loop through the hosts.csv file and for each row, call your function to break the name into parts and look up each part in the translations dict. Create a list of the original name and the translated parts, and output this as a row using the csv module.

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