for the grade only

 Please look over vehicles_v2.py for an abstract base class example using the virtual function/abstract method bs and the abc module from the Python standard library. Please adapt your code for lab07 to include the abc module for abstract base classes and teh decorator @abc.abstractmethod for virtual functions in the parent class that must be overwritten in the child class in order for the code to work without an error. The deadline for the lab has been extended to 11:59pm 11/26.