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: ['3667', '4587', 'P', '3653', '1901', '8163', '1723', '6161', '7979', '4659', '3691', '3933', 'R', '1769', 'l', 'J', 'b', '863']

3667, 4587, 16, 3653, 1901, 8163, 1723, 6161, 7979, 4659, 3691, 3933, 18, 1769, 12, 10, 2, 863