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: ['U', '6585', 'E', '6795', '7625', '7809', 'd', 'R', 'd', 'E']

21, 6585, 5, 6795, 7625, 7809, 4, 18, 4, 5