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', 'j', '4239', 'T', '4345', 'u', '8581', '1977', 'a', '7377', '835', 'i', 'e', 't', '9419', 'I']

4, 10, 4239, 20, 4345, 21, 8581, 1977, 1, 7377, 835, 9, 5, 20, 9419, 9