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', '9895', 'r', 'H', 'C']

SOLUTION: 9895

PROBLEM: ['o', 'a', 'K', '6031']

SOLUTION: 6031

PROBLEM: ['3437', '9747', 'n', '1091']

SOLUTION:
14275