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: ['2315', 'j', 'r', '2073', 'u', 'n', 'R', '6855', 'Y', 'u', 'i', 'Z', 'H', 't']

2315, 10, 18, 2073, 21, 14, 18, 6855, 25, 21, 9, 26, 8, 20