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:
['2175', '4539', 'L', 'T', 'q', '2407', 'F', 'V', 'b', '9475', '2279', '4469', '6231']

Ex Output:
31575


Ex Input:
['4271', 'N', 'M', '5239', '7037', 'x', 'U', 's', '7107', '4163', 'f', '3607', '6155']

Ex Output:
37579


Ex Input:
['i', '7975', 'i', '1985', '2791', '2007']

Ex Output:

14758