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: ['6563', 'R', 'M', 'B', 'b', 'E', '9911', '7327', 'J', '7389', 'w', 'b', 'c', '1527', 'K', 'r', '5441', '6823', '8455']

SOLUTION: 53436

PROBLEM: ['t', '7469', 'Y', 'N', '8137']

SOLUTION: 15606

PROBLEM: ['X', '5087', '7995', 'm', 'm', 'v', 'm']

SOLUTION:
13082