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.

Q: ['8591', 'J', 'l', 'l', '7023', 'N', 'n']

A: 15614
****
Q: ['291', 'R', 'N', '983', '2879', 'C', '3797', '4837', '793', '5489', 'k', '535', 'L', '3605', 's', '3701', 'U', '4399', '2489', '4739']

A: 38537
****
Q: ['4939', 'n', '2231', 's', '7431', '151', 'H', '8963', '7853', '4343', 'i']

A:
35911
****