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:
['901', 'X', 'W', 'D', 'm', 'M', '59', '4855', '6523', 'R', '9781', '8271', '4449', '2221', '8391']

Ex Output:
45451


Ex Input:
['q', 't', '4837', 'F', '2367', '1867', '8361', 'm']

Ex Output:
17432


Ex Input:
['G', 'K', '4543', '9405', '4747', '7821', '5707', 'R', '9391', 'z', 'C', '8235']

Ex Output:

49849