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: ['M', '5857', 'F', 'o', 'k', '113', 'M', 'M', 't', '5535', 'W', 'I', 'H']

13, 5857, 6, 15, 11, 113, 13, 13, 20, 5535, 23, 9, 8