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: ['2039', '1679', '9675', 'S', 'J', '2069', 'r', 'e']

SOLUTION: 15462

PROBLEM: ['2237', '2597', '2593', 'Y', '5345', 'g', 'l', 'I', 'p', 'u', 'L', 'T', '617', '9759', 'b', 'w', '7097', '9863']

SOLUTION: 40108

PROBLEM: ['D', 'x', 'h', 's', 'a', 'm', 'f', '7653']

SOLUTION:
7653