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: ['w', 'I', 't', '813', 'K', '5785']

SOLUTION: 6598

PROBLEM: ['x', 'd', '5121', 'I', '6737', '3789', '6167', 'C', '8947', 'k', '4715', '1885', 'H', 'B', '5685', 'S', '4615', 's', '7709']

SOLUTION: 55370

PROBLEM: ['9837', 'r', 'g', 'E', '645', 'H', 'j', 'i', 'A', '1047', '3195', '7267', '6809', '3941', 'J']

SOLUTION:
32741