Detailed Instructions: 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.
Q: ['a', '4019', '3263', '5351', '1489', '6401', '3537', 'u', '9731', 'U', '5129', '9067', '7289']
A:
1, 4019, 3263, 5351, 1489, 6401, 3537, 21, 9731, 21, 5129, 9067, 7289