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: ['2307', '4921', 'y', '9839', 'i', '5003', 'H', 'J']

2307, 4921, 25, 9839, 9, 5003, 8, 10