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: ['9961', 'Y', '669', '8227', 'j', 'c', '8749', 'c', 'K', '8439']

9961, 25, 669, 8227, 10, 3, 8749, 3, 11, 8439