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: ['a', 'Y', '5941', '5125', '3971', '4749', 'H']

1, 25, 5941, 5125, 3971, 4749, 8