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: ['g', 'M', 'I', 'V', '3377', '7309', '3617', 'v', '9207', 'k', '387', 'g', 'C', '4785', '1527', 'O', 'A']

SOLUTION: 30209

PROBLEM: ['y', 'p', '3553', '2155', 'b', 'R', 'j', 'V', 'U']

SOLUTION: 5708

PROBLEM: ['U', 'm', 'e', 'W', '6143']

SOLUTION:
6143