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: ['7497', 't', '6477', '3097', 'G', '1525', '2371', '4923', 'R', 'a', 'G', 'K', '8789', '5745', 'c', '6303', '1549', 'e', 'a', 'H', 'R', '9547', 'T', 'z', 'K']

7497, 20, 6477, 3097, 7, 1525, 2371, 4923, 18, 1, 7, 11, 8789, 5745, 3, 6303, 1549, 5, 1, 8, 18, 9547, 20, 26, 11