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: ['u', 'a', '9939', '9353', 'v', 'S', 'l', '981', 'P', 'q', 'M', 'w', '8419']

21, 1, 9939, 9353, 22, 19, 12, 981, 16, 17, 13, 23, 8419