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: ['c', '4151', '619', 'm', '623', 'E', '4851', 'C', '5361', '8815', 'L', 'v', 'e', 'd', '1783', 'i', '1095', '7567', '2949', 'U', '8267', 'j', '227', 'o', '9245', 'A', '9987', '2877']

3, 4151, 619, 13, 623, 5, 4851, 3, 5361, 8815, 12, 22, 5, 4, 1783, 9, 1095, 7567, 2949, 21, 8267, 10, 227, 15, 9245, 1, 9987, 2877