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: ['Q', '9787', '7533', '9489', 'C', '1753', '5121', '1405', '9267', '4815', 's', '5887']

SOLUTION: 55057

PROBLEM: ['D', 'b', 'h', 'p', '1637']

SOLUTION: 1637

PROBLEM: ['c', '3117', 'y']

SOLUTION:
3117