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: ['9969', 'S', 'v', 'O', 'N', 'O', 'w', '6015', 'P', 'N', '437', 'v', '9611', '5139', '4509', '1965', 'Z', '5615']

9969, 19, 22, 15, 14, 15, 23, 6015, 16, 14, 437, 22, 9611, 5139, 4509, 1965, 26, 5615