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', '8333', 'C', 'Z', 'n', '1419', 'd', '3205', 'D', '1187', 'd']

SOLUTION: 14144

PROBLEM: ['7669', '3367', 'A', 'Z', '6173', '4391', 'f', 'S', '9657', '2631']

SOLUTION: 33888

PROBLEM: ['2239', 'D']

SOLUTION:
2239