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: ['7187', '5331', '6081', '8217', 'p', 'F', 'F', 'x', '8309', 'B', 'g', '9807', '9405', 't', '5353', '7619', 'H', 'U', 'L', 'A', 'f', '5737', '7517', '8507']

7187, 5331, 6081, 8217, 16, 6, 6, 24, 8309, 2, 7, 9807, 9405, 20, 5353, 7619, 8, 21, 12, 1, 6, 5737, 7517, 8507