How would you make a comma-separated string from a list of strings?

Question

What would be your preferred way to concatenate strings from a sequence such that between every two consecutive pairs a comma is added. That is, how do you map, for instance

Answer 1

I would say the csv library is the only sensible option here, as it was built to cope with all csv use cases such as commas in a string, etc.

To output a list l to a .csv file:

import csv
with open('some.csv', 'w', newline='') as f:
    writer = csv.writer(f)
    writer.writerow(l)  # this will output l as a single row.  

It is also possible to use writer.writerows(iterable) to output multiple rows to csv.

This example is compatible with Python 3, as the other answer here used StringIO which is Python 2.