Questions: trivial Polymorphism dynamically typed vs statically typed (example) what is the difference between, instance, class and static methods (python) python question: given dict {"a": "a", "b": "b"} does function changes the dictionary. correct answer is yes. what should we do to not affect the dict? deep copy of the dictionary end. Airline ticketing system calculate ticketing (cost of operations changes per airline, and cost ticketing changes per airline) airline_list = ['United 150.0 Economy', 'Southwest 150.0 Business', 'American 150.0 Premium',] What if you have 100 airlines with different cost calculations for operations and ticketing. how to tackle this?