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', '6579', 'w', 'X', 'Q', 'e', 'd', '8099', 'r', 'k', 'V', 'S', 'y', '259', 'u', 'h', 't', 'k', '3907', '9823', '4987', '2081', 'a', 'Y', 'z', '591', 'x', 'G', '857', 'x', '4307', 'M', 'U']

4, 6579, 23, 24, 17, 5, 4, 8099, 18, 11, 22, 19, 25, 259, 21, 8, 20, 11, 3907, 9823, 4987, 2081, 1, 25, 26, 591, 24, 7, 857, 24, 4307, 13, 21