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: ['2553', '3201', 'a', '9503', '6621', 't', 'V', 'C', 'w', 't']

2553, 3201, 1, 9503, 6621, 20, 22, 3, 23, 20