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: ['631', '4939', 'F', 'l', '9261', '1999', 'B', '7007']

631, 4939, 6, 12, 9261, 1999, 2, 7007