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: ['e', '8253', '6419', 'x', '4511', '1315', '1581', '3987', 'u', '5423', '5845', '2033', 'C', '7659', 'l', 'U', '1455', '5255', 'w', '9231', 'q', 'k', '903', 'N', '669', '5411', 'u', '7547', '8121']

5, 8253, 6419, 24, 4511, 1315, 1581, 3987, 21, 5423, 5845, 2033, 3, 7659, 12, 21, 1455, 5255, 23, 9231, 17, 11, 903, 14, 669, 5411, 21, 7547, 8121