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: ['T', 'n', '8513', '5565', '6343', '1403', '975', '6959', '8049', '1601', 'j', 'Q', 'O', '7889', 'r', 'D', '1903', '6607']

SOLUTION: 55807

PROBLEM: ['V', 'h', '5549', 'K', 's', '8337', 'Y', '497', 'z', 'T', '4467', '6333', 'M', '1573', 'y', 'O', '5499', 's', 't', '6205']

SOLUTION: 38460

PROBLEM: ['6069', '2743', '9725', 'L', '6917', 'W', '9531', '6875', '5255', 'e', '8035', 'X', '7251', '2927']

SOLUTION:
65328