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: ['m', 'g', '7251', '5873', '59', '7345']

SOLUTION: 20528

PROBLEM: ['f', 'H', 'U', 'l', 'n', 'q', '2701', '339', 'X', 'H', 'O', 'q', '2313']

SOLUTION: 5353

PROBLEM: ['b', '5215', 'Q', 'g', 'f', 'j', '3435', 'g']

SOLUTION:
8650