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: ['2577', 'B', '3059', 'S', 'l', 'T', 'Q', 'x', 'f', 'l', 'y']

SOLUTION: 5636

PROBLEM: ['z', '9173', 's', '8937', 'h', '1881', '7929', 'b', '2441']

SOLUTION: 30361

PROBLEM: ['909', '5903', 'x', 'w', '1717', 'l', '8985', 'T', '4839', 'H']

SOLUTION:
22353