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: ['4949', '2459', 'n', 'f', 'n', 'v', '8421', '1519', '4859', 'c', '9923', '2829', 'K', '4937', 'W', 'R']

SOLUTION: 39896

PROBLEM: ['2039', '1679', '9675', 'S', 'J', '2069', 'r', 'e']

SOLUTION: 15462

PROBLEM: ['g', '1353', '3861', 'm', 'z', '965', 'Y', '2229', 'j', 'p', '5153', 'O', 'F']

SOLUTION:
13561