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: ['D', '7253', '5667', 'Q', 'C', '511', 'D', '8181', 'Y', 'B', '7731', 'Z', 'm', '345', 'C', '2869', 'b', '6669', 'A', 'u', 'c', '9837', 'W', 'j', 'q', 'H']

4, 7253, 5667, 17, 3, 511, 4, 8181, 25, 2, 7731, 26, 13, 345, 3, 2869, 2, 6669, 1, 21, 3, 9837, 23, 10, 17, 8