Public attributes and methods
Name:
Date:
Class:
A
Quick Questions
Shade in the A or B circle for each question.
1. Which attribute is public?
2. Which line reads a public attribute from outside the class (pet is an object)?
3. True or false: a public method can be called from outside the class, e.g. pet.speak().
4. Which method name is public?
5. Which line changes a public attribute from outside the class?
B
Match the Pairs
Draw a line connecting each item on the left to its match on the right.
| Left column | Right column | |
|---|---|---|
| 1self.name = name | AThe attribute is accessed without an object. Outside the class a public attribute needs the object and a dot, like pet.name. | |
| 2def speak(self): | BDefines a public method that can be called from inside or outside the class | |
| 3Code outside the class can read a public attribute using the object name and a dot | CCreates a public attribute with no leading underscore, so any code can read or change it | |
| 4Code outside the class can call a public method on an object | DThe leading underscore makes the attribute protected by convention, not public. Use self.name to make it public. | |
| 5self._name = name # meant to be public | Epet.speak() | |
| 6print(name) # outside the class | Fprint(pet.name) |
C
Definitions
self.name
D
Fill in the Blanks
Complete each line of code by filling in the missing parts.
1.
pet = Pet("Milo")
pet._____()
print(pet.name)
2.
pet = Pet("Milo")
print(___.name)
3.
class Pet:
def speak(____):
print("Woof!")
4.
def intro(self):
____.speak()
5.
pet = ___("Milo")
print(pet.name)
pet.speak()
E
Spot the Error
Shade in the letter of the line that contains an error.
Question 1
A
class Pet:
B
def __init__(self, name):
C
name = name
D
pet = Pet("Rex")
E
print(pet.name)
Question 2
A
class Pet:
B
def __init__(self, name):
C
self.name = name
D
def speak():
E
print(self.name, "woofs")
F
Pet("Rex").speak()
Question 3
A
class Dog:
B
def _bark(self):
C
print("Woof!")
D
rex = Dog()
E
rex.bark()
Question 4
A
class Car:
B
def __init__(self, make)
C
self.make = make
D
car = Car("Kia")
E
print(car.make)
Question 5
A
class Player:
B
def __init__(self):
C
self.__score = 0
D
p = Player()
E
print(p.score)
Answer Key
Public attributes and methods
Section A: Quick Questions
Q1
B — self.name
Q2
A — print(pet.name)
Q3
A — True
Q4
A — def speak(self):
Q5
B — pet.name = 'Rex'
Section B: Match the Pairs
Q1
self.name = name → Creates a public attribute with no leading underscore, so any code can read or change it
Q2
def speak(self): → Defines a public method that can be called from inside or outside the class
Q3
Code outside the class can read a public attribute using the object name and a dot → print(pet.name)
Q4
Code outside the class can call a public method on an object → pet.speak()
Q5
self._name = name # meant to be public → The leading underscore makes the attribute protected by convention, not public. Use self.name to make it public.
Q6
print(name) # outside the class → The attribute is accessed without an object. Outside the class a public attribute needs the object and a dot, like pet.name.
Section C: Definitions
Q1
self.name — A public member has no leading underscore, so code inside or outside the class can access it, e.g. self.name in the class or pet.name outside it.Section D: Fill in the Blanks
Q1
pet = Pet("Milo")
pet.speak()
print(pet.name)Q2
pet = Pet("Milo")
print(pet.name)Q3
class Pet:
def speak(self):
print("Woof!")Q4
def intro(self):
self.speak()Q5
pet = Pet("Milo")
print(pet.name)
pet.speak()Section E: Spot the Error
Q1
C — Without self., this only sets a local variable, so no public attribute is created. It should be self.name = name so pet.name works outside the class.
Q2
D — Every method needs self as its first parameter so it can use self.name. It should be def speak(self):.
Q3
B — The leading underscore means the method is not public, so rex.bark() fails from outside the class. A public method has no underscore: def bark(self):.
Q4
B — The def line is missing its colon. It should be def __init__(self, make): so the public attribute self.make can be set.
Q5
C — The double underscore makes score private, so p.score fails outside the class. A public attribute has no leading underscore: self.score = 0.