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: ['i', 'w', '8117', '2823', 'C', 'x', 'w', '5959', 'g', 'e', 'L', 'V', 'i', 'w', 'n']

SOLUTION: 16899

PROBLEM: ['5021', 'q', '4109', 'g', 'w', 'C', 'w', '239', 'N', '9755', '8591', '7083', 'Q', '7907', 'w', 'U', 'a', '4901', 'k', 'G']

SOLUTION: 47606

PROBLEM: ['873', '2203', 'S', 'q', 'R', '7151', 'h', 'j', 'u']

SOLUTION:
10227