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: ['4529', '7465', 'S', 'Z', 'v', 'w', '5791', '3363', '2643']

SOLUTION: 23791

PROBLEM: ['8667', '4129', '7075', '6345', '1315', 'M', 'F', '9073']

SOLUTION: 36604

PROBLEM: ['7555', '8303', '8157', 'a', 'Q', 'r']

SOLUTION:
24015