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: ['5215', 'c', '839', 'V']

SOLUTION: 6054

PROBLEM: ['4749', '1169', '4273', 'X']

SOLUTION: 10191

PROBLEM: ['C', 'i', 'L', '1777', '3435', '9375', 'B', '605', '1309', '2893', '683', 'F', '6871', 'd', 'b']

SOLUTION:
26948