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', 'L', '9191', 'g', '491', 'z', 'w', 'C', '5575', 'l', '8731', 'K', 'C', 's', 'Q', '7571']

15, 12, 9191, 7, 491, 26, 23, 3, 5575, 12, 8731, 11, 3, 19, 17, 7571