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: ['T', '709', '7055', '3515', 'Z', '1077', 'f', 'a', '4255', 'E', 'd', '2903', '4639', 'L']

20, 709, 7055, 3515, 26, 1077, 6, 1, 4255, 5, 4, 2903, 4639, 12