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: ['C', '4621', 'I', 'J', 'p', 'M', 'E', '5019', '8205', '6069', '8203', '8973', 'a', 's']

3, 4621, 9, 10, 16, 13, 5, 5019, 8205, 6069, 8203, 8973, 1, 19