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: ['2649', 'U', 'x', '9855', '4607', 'I', 'j', '3291', '6239', '5229', 'p', 'L', 'N', 'J', 'x', '4155', '5331', 'K', 'X', '5451', '3483', 'y', 'U', 'M', 'V']

2649, 21, 24, 9855, 4607, 9, 10, 3291, 6239, 5229, 16, 12, 14, 10, 24, 4155, 5331, 11, 24, 5451, 3483, 25, 21, 13, 22