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: ['9445', '7291', 'r', 'g', '1175', '7823', '5507', 'j', '7249', '6335', '3853', 'b', 'u', 'S', '365', 'Z', '7489', 'S', 'W', 'e']

SOLUTION: 56532

PROBLEM: ['z', '3199', 'r', '849', 'C', 'v', '1931', 'M', 'Q', '4531', '579', 'x', '8997', '4663']

SOLUTION: 24749

PROBLEM: ['I', '1941', '2423', '3381', 'J', '6589', 'h', 'D']

SOLUTION:
14334