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: ['7959', '1345', '4605', '6453', 'Q']

SOLUTION: 20362

PROBLEM: ['c', 'a', 'H', '4917', '739', 'C', '6001', '2435', 'q', 'Y', 'J', 'e', 'd', 'j', 'b', '575', '2931', '8405', '9307']

SOLUTION:
35310