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', 'w', 'k', '4867', 'r', 'A', '6683', 'K', '9535', 'L']

21, 23, 11, 4867, 18, 1, 6683, 11, 9535, 12