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: ['2013', 'S', 's', '9353', 'b', 'u', '6687', '5429', '3545', '7269']

SOLUTION: 34296

PROBLEM: ['7771', 'g']

SOLUTION: 7771

PROBLEM: ['Q', '6217', 'e', 'R', '7009', '137', 'v', '957', 'F', '9479', 'K', '7313', 'F', 'U', '2557', 'g', 'J', 'P', '3977']

SOLUTION:
37646