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: ['973', 'J', '3573', 'J', 'I', 'X', '9795', '829', 'N', '4379', 'f', '2949', 'p', '7657', '2657', '6537', '5705', 'x', 'U', '5245', '2011', '1257', 'U', 'q', '6343', '9515']

973, 10, 3573, 10, 9, 24, 9795, 829, 14, 4379, 6, 2949, 16, 7657, 2657, 6537, 5705, 24, 21, 5245, 2011, 1257, 21, 17, 6343, 9515