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: ['7357', 'D', 'S', '3443', 'X', 'B', 'N', '3563', 'W', '5295', '8515', '2711', '9917', 'x', 'B', 'q', 'v', '59', 'B', 'r', '7221', '291']

7357, 4, 19, 3443, 24, 2, 14, 3563, 23, 5295, 8515, 2711, 9917, 24, 2, 17, 22, 59, 2, 18, 7221, 291