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: ['Y', 'X']

SOLUTION: 0

PROBLEM: ['6121', 'S', '8683', 'Y', '6107', 'B', '6193', '5555', '365', '945', '1439', '7257', 'g']

SOLUTION: 42665

PROBLEM: ['2879', '8323', '7085', '2013', '7165', 'b', '5549']

SOLUTION:
33014