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: ['5335', 'q', 'Q', '3409', '6177', 'Q', 'D', 'Y', 'L', '1187', '1997']

5335, 17, 17, 3409, 6177, 17, 4, 25, 12, 1187, 1997