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: ['5667', '425', 'H', '5209', '1007', '3517', 'U', 'Y', 'p', 'B', '2983', '4429', '8121', 'R', 'B', 'A', 'A', '8801', 'h', '5351', 'O', '4719']

5667, 425, 8, 5209, 1007, 3517, 21, 25, 16, 2, 2983, 4429, 8121, 18, 2, 1, 1, 8801, 8, 5351, 15, 4719