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: ['a', 'j', 'v', '619', 't', 'a', '5777', 'x', 'R', 'P', '8897', 'j']

SOLUTION: 15293

PROBLEM: ['V', '2633', '3269', 'r', 'Q', '3517', '2571', 'G', '4105', 'm', 'z', 'B', 'A']

SOLUTION: 16095

PROBLEM: ['B', 'G', 'b', '9817', '263', '4707', 'H']

SOLUTION:
14787