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:
['291', 'R', 'N', '983', '2879', 'C', '3797', '4837', '793', '5489', 'k', '535', 'L', '3605', 's', '3701', 'U', '4399', '2489', '4739']

Ex Output:
38537


Ex Input:
['o', 'O', 'H', '7619', '6435', 'X', 'g', '1663']

Ex Output:
15717


Ex Input:
['m', 'C', 'D', '5103', '9977', '661', 'e', 'a', '2141', 'q', 's', 'E', '9523', 'u', 'd', 'c', '675', 'Y']

Ex Output:

28080