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: ['I', 'O', '2645', '8955', '2723', '6145', '4321', '1095', '2711', '1553', '3861', 'D', 'r', '1731', '6359', '8241', '5395', 'b', 'A', 's', 'P', 'o', '107', 'D', '4653', '7353', 'R', 'S', 'p', 't', 'c', 'i', '6311', '8323']

9, 15, 2645, 8955, 2723, 6145, 4321, 1095, 2711, 1553, 3861, 4, 18, 1731, 6359, 8241, 5395, 2, 1, 19, 16, 15, 107, 4, 4653, 7353, 18, 19, 16, 20, 3, 9, 6311, 8323