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: ['777', '5901', 'R', 'w', 'p', 'S', 'H', '6341', '1035', 'f', '5147', '45', 'a', 'y', 'B', '7535', '6937', 'p', '2465', 'Q', 'A', '8049', '7247', '9999']

777, 5901, 18, 23, 16, 19, 8, 6341, 1035, 6, 5147, 45, 1, 25, 2, 7535, 6937, 16, 2465, 17, 1, 8049, 7247, 9999