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: ['7959', '1345', '4605', '6453', 'Q']

SOLUTION: 20362

PROBLEM: ['817', 'm', 'P', 'R', '8133', '9731', '1085']

SOLUTION:
19766