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: ['s', '425', '6135']

SOLUTION: 6560

PROBLEM: ['4177', 'd', 'b', 'm', 'f', 'R', '797', '7905', '4355', '7515', '9801', 'F', 'R', '9125', '8445', 'k', 'K', 'K']

SOLUTION: 52120

PROBLEM: ['5973', 'F', 'W', '4507', '5347', '9949', 'y', '185', 'w', '4713', '8881', 'E', '1151', 'y', 'f', 'X']

SOLUTION:
40706