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: ['9819', 't', '7209', 'o', '87', '7389', '3191', 'L', 'o', 'R', 'v', 'c', '4413', 'I', '5817', 'r', 'i', 'R', 'D', 'F', '4825', 'u', 'w', 'T', 'l', 'O', 'S', 'T', '7161', '9509', 'P', 'k']

9819, 20, 7209, 15, 87, 7389, 3191, 12, 15, 18, 22, 3, 4413, 9, 5817, 18, 9, 18, 4, 6, 4825, 21, 23, 20, 12, 15, 19, 20, 7161, 9509, 16, 11