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: ['Z', '6245', 'N', '1403', 'b']

SOLUTION: 7648

PROBLEM: ['y', 'F', '135', '7359', '8579', '6809', '3979', 'H', 'm', '5059', '373', 'Y']

SOLUTION: 32293

PROBLEM: ['8961', '8787', 'F', 'O', '1001', '2789', '3987', 'D', '8211']

SOLUTION:
33736