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', '3149', 'f', 'R', 'c', 'Z', 'K', 'n', '2899', 'F', 'e', '6939', 'N', 'e', 'K', '9583']

4, 3149, 6, 18, 3, 26, 11, 14, 2899, 6, 5, 6939, 14, 5, 11, 9583