Duck typing concept in Python - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

What is the output of this duck typing example?

Consider the following Python code using duck typing. What will it print?

Python

class Bird:
    def fly(self):
        return "Flying in the sky"

class Airplane:
    def fly(self):
        return "Flying through clouds"

def lets_fly(thing):
    return thing.fly()

print(lets_fly(Bird()))

A "Flying in the sky"

B TypeError

C AttributeError

D "Flying through clouds"

💡 Hint

Look at which class instance is passed to lets_fly function.

The lets_fly function calls the fly method on the passed object. Since Bird instance is passed, it calls Bird.fly() which returns "Flying in the sky".

❓ Predict Output

intermediate

What happens when an object lacks the expected method?

What will be the output of this code?

Python

class Fish:
    def swim(self):
        return "Swimming in water"

def lets_fly(thing):
    return thing.fly()

print(lets_fly(Fish()))

A "Swimming in water"

B AttributeError

C "Flying in the sky"

D TypeError

💡 Hint

Check if Fish has a fly method.

The lets_fly function calls fly() on the Fish instance, but Fish does not have a fly method, so Python raises AttributeError.

🧠 Conceptual

advanced

Which statement best describes duck typing?

Choose the best description of duck typing in Python.

A Restricting objects to a specific class hierarchy.

B Checking an object's type before using it.

C Using an object's methods and properties without checking its type.

D Using static type annotations to enforce types.

💡 Hint

Think about how Python treats objects based on their behavior, not their type.

Duck typing means you use an object based on whether it has the required methods or properties, not based on its class or type.

❓ Predict Output

advanced

What is the output of this duck typing with multiple objects?

What will this code print?

Python

class Dog:
    def speak(self):
        return "Woof!"

class Cat:
    def speak(self):
        return "Meow!"

def animal_sound(animal):
    return animal.speak()

print(animal_sound(Dog()))
print(animal_sound(Cat()))

A "Woof!\nMeow!"

B "Meow!\nWoof!"

C AttributeError

D TypeError

💡 Hint

Check the order of print statements and which class instances are passed.

animal_sound(Dog()) returns "Woof!" and animal_sound(Cat()) returns "Meow!". They print in that order separated by newline.

🔧 Debug

expert

Why does this duck typing code raise an error?

This code is intended to use duck typing but raises an error. What is the cause?

Python

class Car:
    def drive(self):
        return "Driving fast"

def lets_drive(vehicle):
    return vehicle.drive()

print(lets_drive("fast car"))

A No error, prints "Driving fast"

B TypeError because string has no drive method

C SyntaxError due to missing colon

D AttributeError because string has no drive method

💡 Hint

Check if the string "fast car" has a drive method.

The string "fast car" does not have a drive method, so calling vehicle.drive() raises AttributeError.