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: ['2901', '8121', '4691', 'f', 'm', 'Y', '5849', '6053', 'T', 'j', 'v', '577', 'Y', '9839', 'b', '2451', '5443', '69', 'T', 's', '2663', 'U', 'T', 'W', 'C']

2901, 8121, 4691, 6, 13, 25, 5849, 6053, 20, 10, 22, 577, 25, 9839, 2, 2451, 5443, 69, 20, 19, 2663, 21, 20, 23, 3