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: ['869', 'M', '3575', '7845', '8819', '3981', '327', '3089', '605', '6623', 't', '1645', 'b', '2309', 'k', 'J', 'H', 'g', '8427', 'v', 'l', 'q', '7821', '819']

869, 13, 3575, 7845, 8819, 3981, 327, 3089, 605, 6623, 20, 1645, 2, 2309, 11, 10, 8, 7, 8427, 22, 12, 17, 7821, 819