Definition: In this task, you are given an input list A. You need to convert all the alphabets in the list with a number representing their position in the English alphabet. E.g., replace A by 1, B by 2, a by 1, b by 2, and so on.
Input: ['931', 't', '3449', '7993', 'G', 's', '8985', '2713', 'M', 'p', 'b', '9223', '7847', 'H', '4635', 'v', 'u', 'o', '9979']

931, 20, 3449, 7993, 7, 19, 8985, 2713, 13, 16, 2, 9223, 7847, 8, 4635, 22, 21, 15, 9979