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: ['t', 'y', '135', 'L', 'x', 'p', '6921', 'M', '9557', 'X', '3433', '8149', '7993', 'j', 'o', 'J', '9549', 'Y', 'Y', 'z', '2875', '4307', 'f', 't', 'Y', '8289', 'e', 'p', 'z']

20, 25, 135, 12, 24, 16, 6921, 13, 9557, 24, 3433, 8149, 7993, 10, 15, 10, 9549, 25, 25, 26, 2875, 4307, 6, 20, 25, 8289, 5, 16, 26