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:
['339', 'h', 'd', '7449', 'e', 'u', '5055', '7029', '9009', 'G', 'U', '3', '441', '3273', 'K', '3827', '7069', 'x']

Ex Output:
43494


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

Ex Output:
4501


Ex Input:
['P', 'b', 'F', '3743', '8231', 'n', 'S', 'f', '5451', '1803', 'Z', '1785']

Ex Output:

21013