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: ['9503', '5447', '7761', '5789', 'l', 'G', '6353', '1643', 'l', 'F', 'd', '8645', 'G', 'U', '559', 'p', 'v', '167', 'C', 'k', 'H', '8541', '2865', 'w', 'I', 'c', '4205', 'D', '1823', 'j', 'u', 't']

9503, 5447, 7761, 5789, 12, 7, 6353, 1643, 12, 6, 4, 8645, 7, 21, 559, 16, 22, 167, 3, 11, 8, 8541, 2865, 23, 9, 3, 4205, 4, 1823, 10, 21, 20