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: ['o', '4635', 'v', '2301', 'l', '291', 'u', '707', '1731', '9941', '4825', 'Q', '6513', '8413', 'U', '2621', 'Q', '8555', 'b']

15, 4635, 22, 2301, 12, 291, 21, 707, 1731, 9941, 4825, 17, 6513, 8413, 21, 2621, 17, 8555, 2