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: ['Y', '1891', '4755', '7015', '335', 'Z', 'W', '5993', '2665', 'k', '5987', 'e', '7601', '4579', 'i', 'y', 'S', '5453', 'E', 'u', 'Q', '1237', '1763', 'H', 'q', 't', 's', 'T', 'e']

25, 1891, 4755, 7015, 335, 26, 23, 5993, 2665, 11, 5987, 5, 7601, 4579, 9, 25, 19, 5453, 5, 21, 17, 1237, 1763, 8, 17, 20, 19, 20, 5