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: ['Z', '6635', 'f', 'j', '109', '1541', 'h', '1199', 'm', '2339', '1721', 'C', '5925', '6979', '4555', 'A', '6207', '8619', '6775', 'F', '3305', 'H', 'i', '5645', 'p', 'w', 'b', 'G', 'n', '43', '1211', '6777', '6297', '1643', 'U']

26, 6635, 6, 10, 109, 1541, 8, 1199, 13, 2339, 1721, 3, 5925, 6979, 4555, 1, 6207, 8619, 6775, 6, 3305, 8, 9, 5645, 16, 23, 2, 7, 14, 43, 1211, 6777, 6297, 1643, 21