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: ['h', 'a', '469', 'H', 'F', 'E', '1343', '4689', 'p', '7947', 'n', '5403', 'y', '3159']

8, 1, 469, 8, 6, 5, 1343, 4689, 16, 7947, 14, 5403, 25, 3159