Сообщите мне, поможет ли это:
with open('friends.txt', 'r') as input_file, open('OUTPUTFILE', 'w') as sorted_output:
data = input_file.readlines()
d = ["{0},{1}".format(i.strip().split(",")[0], i.strip().split(",")[3]) for i in data]
sorted_output.write("\n".join(d))
Вот мой файл ввода / вывода:
John,555-234-9876,May 5,123
Mary,556-987-2367,December 12,123
Albert,555-987-6765,June 12,123
Leo,555-789-9865,February 25,123
Ruth,555-786-1238,October 2,123
Fred,556-235-4536,June 17,123%
John,123
Mary,123
Albert,123
Leo,123
Ruth,123
Fred,123