In this task, you are given an input list A. You need to find all the elements of the list that are numbers and calculate their sum.

Ex Input:
['8667', '4129', '7075', '6345', '1315', 'M', 'F', '9073']

Ex Output:
36604

Ex Input:
['G', 'e', 'R', '4427', '3401', '3065', 'I', '2781', '6829', '5261']

Ex Output:
25764

Ex Input:
['R', 'D', '703', '5311', 'G', 'D', 'b', '7713', '4813']

Ex Output:
18540