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: ['p', '8157', 'Y', '1069', 'e', '5941', 'm', '2975', '1529', 'S', 'k', 'm', 'm', '9163', '9659', 'C', '3501', '7857', 'f', 'x', 'Q', '8357', '9469', 't', '8535', 'z', 'R']

16, 8157, 25, 1069, 5, 5941, 13, 2975, 1529, 19, 11, 13, 13, 9163, 9659, 3, 3501, 7857, 6, 24, 17, 8357, 9469, 20, 8535, 26, 18