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: ['D', 'D', '5891', '5845', 'B', 'l', 'u', 'p', 'w', 'p', '5159']

4, 4, 5891, 5845, 2, 12, 21, 16, 23, 16, 5159