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: ['g', '5301']

SOLUTION: 5301

PROBLEM: ['433', 'y', '2015', '5997', 'X', 'u', '9321', '8037', 'N', 'Z', 'E', '4645', '627', '6595', '7679']

SOLUTION: 45349

PROBLEM: ['U', 'z', 'i', '5585', '8389', 'P', 'z', 'E']

SOLUTION:
13974