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: ['K', '5815', 'E', 'c', '7379', '4995', 'w', 'B', 'j', '6227', 'B', '733', '1491', '3191', '9413', '2751', 'O', 'J', '6239', '3521']

SOLUTION: 51755

PROBLEM: ['3723', 'v', 'j', 'e', '2017', 'd', '4211', '2079']

SOLUTION: 12030

PROBLEM: ['O', '7445', '1067', 'y', 'r', 'z', '3809', 'z', '7967', 'h', '7577']

SOLUTION:
27865