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: ['D', '9679', 'e', '5537', 'G', 'l', '2653', 'a', 'Y', '8467', 'q', 'L', '7239', 'O']

SOLUTION: 33575

PROBLEM: ['a', 'q', '4085', '6327', '6869', 'Z', 't', '7057', '1965', 'p', 'o']

SOLUTION: 26303

PROBLEM: ['n', '6729', 'p', 'D', 'o', '1213', 'e', '6951', '2341', '9997', 'e', 'M', 'x', 'R']

SOLUTION:
27231