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: ['6311', '7567', '503', '575', '3477', '5303', '6739', 'f', 'N', '9239', 'c', 'l', 'S', 'h', 'Y', 'b', 'S', '7891', 'i', 'm', '9219', '4255', '6961', 'W', 'T', 'o', '137', '2401', 'd', '1541', 'X', 'D']

6311, 7567, 503, 575, 3477, 5303, 6739, 6, 14, 9239, 3, 12, 19, 8, 25, 2, 19, 7891, 9, 13, 9219, 4255, 6961, 23, 20, 15, 137, 2401, 4, 1541, 24, 4