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: ['C', '1529', '8567', '485', 'C', 'U', 'm', '1909', 'O', '6625', '9387', 'v', 'i', 'v', 'U']

3, 1529, 8567, 485, 3, 21, 13, 1909, 15, 6625, 9387, 22, 9, 22, 21