Lecture 8

Class Definition

Which of the following is a good and valid definition for a class representing a car?

Class Instance

Using the class definition below, which line creates a new Car object with 4 wheels and 2 doors?

class Car(object):
    def __init__(self, w, d):
        self.wheels = w
        self.doors = d
        self.color = ""

Methods

Which of the following methods changes the color of the car, based on the definition below?

class Car(object):
    def __init__(self, w, d):
        self.wheels = w
        self.doors = d
        self.color = ""

 def paint(c):
    color = c

def paint(self, c):
    color = c

def paint(c):
    self.c = c

def paint(self, c):
    self.color = c

Method Call

You create a car with mycar = Car(4, 2). Which is a line of code to change the color of mycar to "red"?

class Car(object):
    def __init__(self, w, d):
        self.wheels = w
        self.doors = d
        self.color = ""
    def paint(self, c):
        self.color = c

Special Methods

With the code below, what does the line print(mycar == yourcar) print?

class Car(object):
    def __init__(self, w, d):
        self.wheels = w
        self.doors = d
        self.color = ""
    def paint(self, c):
        self.color = c
    def __eq__(self, other):
        if self.wheels == other.wheels and \
            self.color == other.color and \
            self.doors == other.doors:
            return True
        else:
            return False

mycar = Car(4, 2)
mycar.paint("red")
yourcar = Car(4,2)
print(mycar == yourcar)