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: ['I', 'n', '3069', '477', 'F', 'k', '847', '6777', 'N', 'X', 'F', '1417', '9445', 'o', 'v', 'd', '2169', 'w']

SOLUTION: 24201

PROBLEM: ['z', 'T', 'Y', 's', 'j', '585', '7833', '2601', '8057', 'S', '7037', '5799', '4477', '5377', '6301', 'P', 'm', '9431', 'f']

SOLUTION: 57498

PROBLEM: ['2563', 'S', 'Z', 'U', '2601', 'l', 'e']

SOLUTION:
5164