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: ['1893', '3357', '3907', '8523', 'e', '9107', 'L', '6053', '9149', 'd', 'I', 'j', 'e', 'u', '9543', '5497', '261', 'u']

1893, 3357, 3907, 8523, 5, 9107, 12, 6053, 9149, 4, 9, 10, 5, 21, 9543, 5497, 261, 21