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: ['A', 'S', 'c', 'I', 'M', 'P', '8739', '879', '1401', '3941', '4061', 'q', 'P', '2805', '4473']

SOLUTION: 26299

PROBLEM: ['3683', 'U', 'x', '313', 'n', '3837', '3299', '2081', '2773', 'r', 'O', '257', '6647', '585', 'o']

SOLUTION: 23475

PROBLEM: ['8313', 'x', '915', '4929', '4413', '4845', '7585', '2311', '9415', '755', '4919', '1871', '8977', '4521', 'J', '4735', '7203', 'b']

SOLUTION:
75707