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: ['N', 'e', '4283', '3243', '5581', '1407', 'q', 'y', '6685', 'v', 'c', '5995']

SOLUTION: 27194

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

SOLUTION: 33575

PROBLEM: ['O', '545', 'A', 'R', '7467', 'G', '5731', '5113', 'X', '3975', '7587', 'O', 'o', 'l', 'u']

SOLUTION:
30418