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: ['R', '8515', 'A', '4787', 'A', '4287', 'F', '5089', 'q', 'N', 'z', '603', '4905', '6141', 'y', '6999', '2171', 'S', '5831', '3353', '9335', 'I', '1437', 'h', '2375', '5637', 'r', 'W', '1787', '5167', 'o', 'n', '857', 'H', '4447', '8911', '9193']

18, 8515, 1, 4787, 1, 4287, 6, 5089, 17, 14, 26, 603, 4905, 6141, 25, 6999, 2171, 19, 5831, 3353, 9335, 9, 1437, 8, 2375, 5637, 18, 23, 1787, 5167, 15, 14, 857, 8, 4447, 8911, 9193