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: ['135', 'a', 'X', '8067', '8447', '4009', '4221', 'o', 'A', 'x']

SOLUTION: 24879

PROBLEM: ['2691', '3861', '7087', '4661', '6527']

SOLUTION: 24827

PROBLEM: ['4219', '2767', '1793', '2211', 'V', 'o', 'g', 'h', 'n', 'S', 'V', '3417', 'E', 'b', 'w', '7197']

SOLUTION:
21604