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: ['1343', 'S', 'E', 'M', 'n', 'C', '7143', '2009', 'V', '6453', '4743', 'l', 'a', 'g', 'M', 'L', '7935', '4609', '925', '3749', '8365', '3361', 'N', '2801', '8915', '6533', 'A', '1231', '4615', 'g', '4013']

1343, 19, 5, 13, 14, 3, 7143, 2009, 22, 6453, 4743, 12, 1, 7, 13, 12, 7935, 4609, 925, 3749, 8365, 3361, 14, 2801, 8915, 6533, 1, 1231, 4615, 7, 4013