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: ['Z', '6149', 'c', 'F', '2939', 'm', '7473', '737', 'n', 'n', 'p', 'V', 'M', 'b', '8639', '4529', '51', '4003']

26, 6149, 3, 6, 2939, 13, 7473, 737, 14, 14, 16, 22, 13, 2, 8639, 4529, 51, 4003