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: ['2175', '4539', 'L', 'T', 'q', '2407', 'F', 'V', 'b', '9475', '2279', '4469', '6231']

SOLUTION: 31575

PROBLEM: ['3629', '8785', '9537', '8479', '3523', 'c', 'C', '5093', '2405', 'y', '1145', '8987', 'f']

SOLUTION: 51583

PROBLEM: ['6127', 'Z', 'T', '7557', 'Y', '9477', 'I', 'u']

SOLUTION:
23161