In Python: Create a base class called car with name, max_speed, and tank_size attributes. Then create a derived class called van that inherits from the car class. The van should have an additional attribute called seating_capacity with default value of 5. The child class should have a method named range to calculate fuel efficiency - the calculation should be: max_speed * seating_capacity * tank_size. Override the method such that it can accept 1, 2 or 3 positional arguments.