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: ['r', 'e', '4069', '149', '4247', 'c', 't', '6787', 'n', '435', 'P', '2379', 'T', '3997', '2307', 'b', '5929', 'J', '4861', '6429', '865', 'C', '1025', '7267', '641', 'Y', 'f', '8293', '407', 'm', 'p', 'v']

18, 5, 4069, 149, 4247, 3, 20, 6787, 14, 435, 16, 2379, 20, 3997, 2307, 2, 5929, 10, 4861, 6429, 865, 3, 1025, 7267, 641, 25, 6, 8293, 407, 13, 16, 22