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: ['2039', '1679', '9675', 'S', 'J', '2069', 'r', 'e']

SOLUTION: 15462

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

SOLUTION: 55057

PROBLEM: ['R', 'T', 'b', 'E', '4683', 'd', '8471', 'b', '4999', 'c', '3165', '9231', '7151']

SOLUTION:
37700