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: ['m', '3481']

SOLUTION: 3481

PROBLEM: ['4159', 'H', 'h', 'W', 'w', 'i', 'G', 'l', 'j', '5467', '9219', 'j', 'q', 'n', '5465', '6197', 'J', 'y']

SOLUTION: 30507

PROBLEM: ['J', 'h', '1869', '2245', 'b', '4113', 'u', 'F', '8245', '8333', '1379', '871', '6089']

SOLUTION:
33144