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: ['t', '8187', 'r', 'S', 'X', '6683', 'F', 'u', '4635', '9497', 'B', 'B', '7277', '2063', '7483', 'S', '9933']

20, 8187, 18, 19, 24, 6683, 6, 21, 4635, 9497, 2, 2, 7277, 2063, 7483, 19, 9933