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: ['E', '2857', '7369', 'N', 's', '5371', 'j', '7021', 'G', 'W', 'd', 'I', 'U', '5879', '5119', 'b', '9479', 'l', 'Z', 'X', 'h']

5, 2857, 7369, 14, 19, 5371, 10, 7021, 7, 23, 4, 9, 21, 5879, 5119, 2, 9479, 12, 26, 24, 8