Run the whole thing as a script, will handle duplicate filenames.

rename_ivr.py

#!/usr/bin/env python
import os
import sys
import csv


def rename_files(csv_filename):
    with open('CS_IVR_NOTES.csv', 'r') as csvfile:
        csvreader = csv.reader(csvfile, delimiter=',', quotechar='"')

        files_mapping = {}
        new_filenames = set()

        for row in csvreader:
            name = row[0] + '.wav'
            new = row[1] + '.wav'

            if new in new_filenames:
                raise Exception(
                    'Found duplicate filename {} for file {}'.format(new, name)
                )

            new_filenames.add(new)
            files_mapping['name'] = new

        for name, new in files_mapping.items():
            if os.path.exists(name):
                os.rename(name, new)
            else:
                print(name + " does not exist")


if __name__ == "__main__":
    rename_files(sys.argv[1])

On the command line, run

chmod +x ./rename_ivr.py 

assuming you're in the same directory as the script to make it executable.

Then to run it you can do:

./rename_ivr.py CSV_FILENAME

hmmm i'm getting the following return:

=========== RESTART: /Users/alexbird/Python/workflow/rename_ivr.py =========== Traceback (most recent call last): File "/Users/alexbird/Python/workflow/rename_ivr.py", line 36, in <module> rename_files(sys.argv[1]) IndexError: list index out of range

I'm not familiar with using sys.argv[n]