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:
['d', '7305', '8903', 'b', '7687', '6393', '6939']

Ex Output:
37227


Ex Input:
['c', '4501', 'O']

Ex Output:
4501


Ex Input:
['7835', 'V', '4449', '823', '4413', 'n', '5049', '9823', 'P', 'g', '6729', 'f', '4701', '7909', '4815', '1819']

Ex Output:

58365