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: ['7217', 'B', 'e', '879', 'm', '4283', '1453', 'N', 'c', '733', 'b', 'u', 't', 'f', 'n', 'Q', 'G', 'U', '6827', '8441', '2241', 'r', '6043', 'x', 'M', 'R', '3079', '3951', '1213', 'j']

7217, 2, 5, 879, 13, 4283, 1453, 14, 3, 733, 2, 21, 20, 6, 14, 17, 7, 21, 6827, 8441, 2241, 18, 6043, 24, 13, 18, 3079, 3951, 1213, 10