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: ['6437', 'N', 'E', 'R', '2841', 'L', '4825', '6807', 'h', '5267', 'o', '2067', '3753', 'X', 'N', 'x', '3387', 'b', 'x', 'C', '2253', 'G', 's', '775', '2851', '945', 'f', '9359', 'b', 'y', 'F', 'P', '1405', '5709', '9995', 'd', 'G']

6437, 14, 5, 18, 2841, 12, 4825, 6807, 8, 5267, 15, 2067, 3753, 24, 14, 24, 3387, 2, 24, 3, 2253, 7, 19, 775, 2851, 945, 6, 9359, 2, 25, 6, 16, 1405, 5709, 9995, 4, 7