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: ['x', '1305', 'b', '8193']

SOLUTION: 9498

PROBLEM: ['g', '5301']

SOLUTION: 5301

PROBLEM: ['k', '2693', '3591']

SOLUTION:
6284