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', '4449', '8559', '5749', 'E', '4573', '3973', '9693', '5247', 'a', '5911', '1941', 'v', '7971']

4, 4449, 8559, 5749, 5, 4573, 3973, 9693, 5247, 1, 5911, 1941, 22, 7971