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: ['e', 'z', '7021', 'S', 'i', '5711', 'v', 'd', 'C', '8933', '6969', '1735', '6429', '399', '5697', 'i', 'Y', '1687', '7073', 'u', '4255', '5935', '961', 'D']

5, 26, 7021, 19, 9, 5711, 22, 4, 3, 8933, 6969, 1735, 6429, 399, 5697, 9, 25, 1687, 7073, 21, 4255, 5935, 961, 4