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: ['615', 'R', '7643', '9401', 'R', '3937', 'B', 'S', 'H', '3967', '1853', 'V', 'i', '3935', 'U', 'U', '9079', '1853', 'G', 'W', 'H', 'v', '8207', '9785', 'D', 'G', 'r', 'L', 'c', 'q', 'n', 'Y', 'p', '823', 'g']

615, 18, 7643, 9401, 18, 3937, 2, 19, 8, 3967, 1853, 22, 9, 3935, 21, 21, 9079, 1853, 7, 23, 8, 22, 8207, 9785, 4, 7, 18, 12, 3, 17, 14, 25, 16, 823, 7