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: ['U', 'u', 'B', 'k', 'Z', 'S', 'a', 'P', '4911', '6873', '1451', 'i', '5671', '3917', 'f', '4895', '837', 'u', 'q', '7127', 'u', '943', 'K', 'n', 'k', '8295']

21, 21, 2, 11, 26, 19, 1, 16, 4911, 6873, 1451, 9, 5671, 3917, 6, 4895, 837, 21, 17, 7127, 21, 943, 11, 14, 11, 8295