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: ['F', 's', 'l', 'e', 'y', '5871', '5237', 'G', '7345', 'f', 'A', '4797', '6919', 's', '9955', 'G', 'y', '1793', 'M']

6, 19, 12, 5, 25, 5871, 5237, 7, 7345, 6, 1, 4797, 6919, 19, 9955, 7, 25, 1793, 13