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: ['6891', '3733', 'I', '3797', '2601', '2285', 'c', 'A', 'A', 'b', '3795', 'P', '8671', 'p', 't', 'c', '7035', 'N', '6801', 'O', '1095', 'W', 'R', '4761', '4199', '3041', 'M', '7973', 'Y', '1619', '8561', '1559', '5097', '3819', '8537', 'O']

6891, 3733, 9, 3797, 2601, 2285, 3, 1, 1, 2, 3795, 16, 8671, 16, 20, 3, 7035, 14, 6801, 15, 1095, 23, 18, 4761, 4199, 3041, 13, 7973, 25, 1619, 8561, 1559, 5097, 3819, 8537, 15