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: ['u', '4873', 'K', 'V', '7441', '5883', '5443', '1025', '2609', 'L']

21, 4873, 11, 22, 7441, 5883, 5443, 1025, 2609, 12