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: ['5585', 'k', 'U', '6151', '5751', '9509', 'i', 'x', '4339', '9213', '435', '4301', '3815', 'H', 'H', 'R', 'u', 'P', 'G', '9593', '1499', '9373', '9299', '5859']

5585, 11, 21, 6151, 5751, 9509, 9, 24, 4339, 9213, 435, 4301, 3815, 8, 8, 18, 21, 16, 7, 9593, 1499, 9373, 9299, 5859