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: ['3839', 'D', '4741', 'L']

SOLUTION: 8580

PROBLEM: ['3145', 'C', '7725', 'k', 'z']

SOLUTION: 10870

PROBLEM: ['N', 'e', '4283', '3243', '5581', '1407', 'q', 'y', '6685', 'v', 'c', '5995']

SOLUTION:
27194