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: ['k', 'C', 'F', 'O', 'U', 't', '3041', 'f', '3997']

11, 3, 6, 15, 21, 20, 3041, 6, 3997