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: ['B', 'L', '8999', '4119', 'q', 'c', '9681', 'Z', 'y', '539', '9583', '1023', '5963', '5429', 'r', 'O', '3553', 'Y', 'P', '2563', 'H', 'D', 'a', 'Z', '8293', '1455', '2415', 'a', 'T', '91', '2187', '6331', '3283', 'h', 'a', '8061', '2307', '4161', 'W', 'g']

2, 12, 8999, 4119, 17, 3, 9681, 26, 25, 539, 9583, 1023, 5963, 5429, 18, 15, 3553, 25, 16, 2563, 8, 4, 1, 26, 8293, 1455, 2415, 1, 20, 91, 2187, 6331, 3283, 8, 1, 8061, 2307, 4161, 23, 7