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: ['2913', 'b', 'j', '7591', 'O', 's', '5589', '4995', '7503', 'U', 'S', 'C', '6797']

SOLUTION: 35388

PROBLEM: ['5215', 'c', '839', 'V']

SOLUTION: 6054

PROBLEM: ['n', '805', '7509', 'z', '7681', '4519', 'k', '1621', 'M', '8853', '7961', 'u', 'E', 'o', 'W', 'Q', 'U', '1275', '6915', '6859']

SOLUTION:
53998