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: ['5521', 'U', '5671', '8975', 'A', '6437', 'J', 'D', '6477', 'p', '4365', 'i', 'T', 'X']

5521, 21, 5671, 8975, 1, 6437, 10, 4, 6477, 16, 4365, 9, 20, 24