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: ['2663', '1067', '4885', '2943', '9879', '1083', 'u', '1057']

2663, 1067, 4885, 2943, 9879, 1083, 21, 1057