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: ['285', '7249', 'P', '2435', '745', 'L', '2455', '49', 'n', '339', '9909', '9597', '5859', 'A', '3341', '9067', 'G', 'a']

285, 7249, 16, 2435, 745, 12, 2455, 49, 14, 339, 9909, 9597, 5859, 1, 3341, 9067, 7, 1