def create_instance(self, carname):
     ''' look for the carname in the autos dictionary
         If it finds one it will return it, else it will create and instance of the nullcar
     '''
     if carname in self.autos:
         return self.autos[carname]()
     else:
         return autos.NullCar(carname)
 def create_instance(self, carname):
     if carname in self._autos:
         return self._autos[carname]()
     else:
         return autos.NullCar(carname)