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: ['3809', '9401', '63', '5705', 'u', '6275', 'k', 'l', '1171', '9365', 'L', 'O', '7431', '8567', 'h', '6135']

SOLUTION: 57922

PROBLEM: ['1875', '9833', 'i', '7493', 'J', 'P', 'z']

SOLUTION: 19201

PROBLEM: ['1651', 'y', 'M', '2313', 'w', 'j', 'T', 'R', '7671', 'Z', '4461', '7883', '2275', 'C', '391', 'o', 'y', '5757', 'U']

SOLUTION:
32402