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: ['R', '4841', '221', 'p', 'K', '8845', '1765', '7773', 'D', '9859', '8781', 'n', 'J', 's', 'N', '221', '6879', '1257', 'a', 'O', '393', '7189']

18, 4841, 221, 16, 11, 8845, 1765, 7773, 4, 9859, 8781, 14, 10, 19, 14, 221, 6879, 1257, 1, 15, 393, 7189