TASK DEFINITION: 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.
PROBLEM: ['i', 'A', 'a']

SOLUTION: 0

PROBLEM: ['6347', '5495', '169', '9503', 'H', '571', '6105', 'X', 'r', 'e', '7369', 'a', 'd', '6999']

SOLUTION: 42558

PROBLEM: ['8229', 'h', 'f', '2493', '7919', '1749', 'V', '2535', '7223', 'y', '8117']

SOLUTION:
38265