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: ['9679', '4125', 'H', 'p', '1851', 'U', '5363', '8683', '6133', 'c', '2543', '879', '8887', '715', 'L', 'A', '8401', 'X', '6165', 'U', 'z']

9679, 4125, 8, 16, 1851, 21, 5363, 8683, 6133, 3, 2543, 879, 8887, 715, 12, 1, 8401, 24, 6165, 21, 26