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: ['A', '6307', 'n', 'U', '5179', 'X', 'N', '767', '8273', 'r', '7055', '9371', 'u', '7479', 'p', '9961', '3547', 'X', '8445']

1, 6307, 14, 21, 5179, 24, 14, 767, 8273, 18, 7055, 9371, 21, 7479, 16, 9961, 3547, 24, 8445