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: ['2621', '8811', '3613', '7469', 'O', 'P', '3429', '6091', 'l', '6905', '8189', '8933', 'l', '1745', 'c', 'a', '8665', '9733', '8263', 'X', '5065', 'W', '1837', 'K', 'k', '519', '7623']

2621, 8811, 3613, 7469, 15, 16, 3429, 6091, 12, 6905, 8189, 8933, 12, 1745, 3, 1, 8665, 9733, 8263, 24, 5065, 23, 1837, 11, 11, 519, 7623