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: ['b', '9615', '4275', 'C', '1601', '5169', '4419', 'U', 'f', '6959', 'Q', '5013', 'v', '5725', '3249', '9351', 'q', '3585', '5143', '9471', '5753', '4279']

2, 9615, 4275, 3, 1601, 5169, 4419, 21, 6, 6959, 17, 5013, 22, 5725, 3249, 9351, 17, 3585, 5143, 9471, 5753, 4279