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: ['D', 'R', 'Y', '4929', 'P', '7929']

SOLUTION: 12858

PROBLEM: ['7379', 'I', '2031', '8419', 'w', 'b', '9827', 'X', 'Y', 't', '3789', 'B', 'c', '6599', 'F', '6169', 'V']

SOLUTION: 44213

PROBLEM: ['O', '7679', 'i', '4031', 'N', 'w', 'q', '1713', '3897', 'o', '8223', 'j', 'e', 'J']

SOLUTION:
25543