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: ['h', '6937', 'U', 'f', 'S', 'm', '9699', 'E', '4559', 'p', 'Z', 'o', '6409', 's', '4537', '5135', '6901', '6489', '5833', 'l']

SOLUTION: 56499

PROBLEM: ['9401', 'w', 'b', '8287', 'n', 'O', 'H', 'h', '45', '2337']

SOLUTION: 20070

PROBLEM: ['P', '309', '4171', 'q', 'k', '8431', '6475', '395', '9243', 'R', '3795', '7509', '5777', '6239', 'w', '9863', '853']

SOLUTION:
63060