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:
['X', 'P', 'x', '9471', '5', 'c', 'f', '5077', '1085', '2267', 'R', 'q', '4987', '9529', 'H', 'n', 'r', 'u']

Ex Output:
32421


Ex Input:
['1203', '6179', '9835']

Ex Output:
17217


Ex Input:
['6735', '3891', 'J', 'L', '9507', 's', '4171', 'Q', '5879', '2121', 'p', '7031', 'R', 'N', '2979', '9475']

Ex Output:

51789