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:
['W', 'H', 'k', 'L', '2425']

Ex Output:
2425


Ex Input:
['5199', 'h', 'T', 'T', 'l', '1661', 'p']

Ex Output:
6860


Ex Input:
['9827', '909', 'l', 'Z', 'r', '2739', '9733', 'H', 'g', '1807']

Ex Output:

25015