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', 'O', 'p', '4219', 'J', 'L', '7453', 'f', 'G', 'b', 'w', '1985', 'f', 'K', '1469', 'M', 't', '1767', 'B', 'j']

4, 15, 16, 4219, 10, 12, 7453, 6, 7, 2, 23, 1985, 6, 11, 1469, 13, 20, 1767, 2, 10