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:
['B', 'K', '9399', 't', '5541', 'w', '1939', '7841', 'q']

Ex Output:
24720


Ex Input:
['4749', '1169', '4273', 'X']

Ex Output:
10191


Ex Input:
['3475', '41', '651']

Ex Output:

4167