Multiple inheritance syntax in Python - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

Output of multiple inheritance method call

What is the output of this Python code using multiple inheritance?

Python

class A:
    def greet(self):
        return "Hello from A"

class B:
    def greet(self):
        return "Hello from B"

class C(A, B):
    pass

obj = C()
print(obj.greet())

A Hello from A

B Hello from B

C Hello from C

D TypeError

💡 Hint

Remember Python uses method resolution order (MRO) and looks for methods in the first parent class listed.

Class C inherits from A and B. Since A is listed first, its greet method is used.

❓ Predict Output

intermediate

Output when overriding method in multiple inheritance

What will this code print?

Python

class X:
    def action(self):
        return "Action from X"

class Y:
    def action(self):
        return "Action from Y"

class Z(X, Y):
    def action(self):
        return super().action()

obj = Z()
print(obj.action())

A Action from X

B AttributeError

C Action from Z

D Action from Y

💡 Hint

super() in class Z calls the next method in the MRO after Z.

super() calls X's action method because X is the first parent in the MRO after Z.

❓ Predict Output

advanced

Output of diamond inheritance with super()

What is the output of this code involving diamond inheritance?

Python

class Base:
    def greet(self):
        return "Hello from Base"

class Left(Base):
    def greet(self):
        return "Left says " + super().greet()

class Right(Base):
    def greet(self):
        return "Right says " + super().greet()

class Child(Left, Right):
    def greet(self):
        return "Child says " + super().greet()

obj = Child()
print(obj.greet())

A Child says Left says Hello from Base

B Child says Right says Left says Hello from Base

C Child says Left says Right says Hello from Base

D TypeError

💡 Hint

Check the method resolution order (MRO) for Child and how super() calls chain.

The MRO is Child > Left > Right > Base. Each greet calls super().greet(), so the output chains accordingly.

❓ Predict Output

advanced

Error raised by incorrect multiple inheritance syntax

What error does this code raise?

Python

class A:
    pass

class B:
    pass

class C(A, B):
    pass

A No error

B TypeError

C NameError

D SyntaxError

💡 Hint

Check the syntax for listing multiple parent classes.

Parent classes must be separated by commas. Missing comma causes SyntaxError.

🧠 Conceptual

expert

Order of classes in multiple inheritance affects method resolution

Given these classes, which option shows the correct method resolution order (MRO) for class D?

class A: pass
class B(A): pass
class C(A): pass
class D(B, C): pass

A [D, A, B, C, object]

B [D, B, C, A, object]

C [D, C, B, A, object]

D [D, B, A, C, object]

💡 Hint

Python uses C3 linearization for MRO. The order of parents in class D matters.

For class D(B, C), MRO is D, B, C, A, object. B before C because B is listed first.