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: ['j', '5075', 'R', 'I', 'y', '7405', '5539', '6463', '8961', '1803', '8897', '1929', 'E', 'N', '9433', 'C']

10, 5075, 18, 9, 25, 7405, 5539, 6463, 8961, 1803, 8897, 1929, 5, 14, 9433, 3