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: ['4155', 'H', 'H', '9377', 'L', '9509', 't', 'Q', 'd', '9431', 'O', 'V', 'n', 'H', 'L', 'J', 'p', '5663', '5231', 'l', 'I', 'L', '4537', '1035', '9015', 'J', '2925', 'M', 'Q', 't', '3335', 't', '1239']

4155, 8, 8, 9377, 12, 9509, 20, 17, 4, 9431, 15, 22, 14, 8, 12, 10, 16, 5663, 5231, 12, 9, 12, 4537, 1035, 9015, 10, 2925, 13, 17, 20, 3335, 20, 1239