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: ['L', 'K', 'W', '3071', 'K', '6431', '4979', '2931', 'p', '2841', '511', '5975', 'z', '9047']

12, 11, 23, 3071, 11, 6431, 4979, 2931, 16, 2841, 511, 5975, 26, 9047