Type checking using type() in Python - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

Output of type() with mixed types

What is the output of this Python code?

Python

values = [42, 3.14, 'hello', [1, 2, 3]]
result = [type(v).__name__ for v in values]
print(result)

A ['int', 'int', 'str', 'list']

B ['int', 'float', 'str', 'list']

C ['int', 'float', 'string', 'list']

D ['int', 'float', 'str', 'tuple']

💡 Hint

Use type() and __name__ attribute to get the type names as strings.

The list contains an int, a float, a string, and a list. type() returns the exact type, and __name__ gives the type name as a string. So the output is ['int', 'float', 'str', 'list'].

❓ Predict Output

intermediate

Type checking with type() and condition

What will be printed by this code?

Python

x = 10
if type(x) == int:
    print('Integer')
else:
    print('Not integer')

A Integer

B Not integer

C TypeError

D SyntaxError

💡 Hint

Check if x is exactly an int using type().

x is assigned 10, which is an int. The condition type(x) == int is True, so it prints 'Integer'.

❓ Predict Output

advanced

Output of nested type() checks

What is the output of this code snippet?

Python

def check_type(val):
    if type(val) == list:
        return 'List of length ' + str(len(val))
    elif type(val) == dict:
        return 'Dict with keys ' + ','.join(val.keys())
    else:
        return 'Other type'

print(check_type({'a':1, 'b':2}))

A Dict with keys ['a', 'b']

B TypeError

C Other type

D Dict with keys a,b

💡 Hint

Check how keys() returns a view and how join expects strings.

val.keys() returns dict_keys(['a', 'b']), which can be joined by ',' to form 'a,b'. So the returned string is 'Dict with keys a,b'.

❓ Predict Output

advanced

Type checking with inheritance and type()

What will this code print?

Python

class Animal:
    pass

class Dog(Animal):
    pass

pet = Dog()
print(type(pet) == Animal)

A False

B True

C TypeError

D SyntaxError

💡 Hint

type() checks exact type, not inheritance.

pet is an instance of Dog, so type(pet) is Dog, not Animal. Therefore, type(pet) == Animal is False.

🧠 Conceptual

expert

Understanding type() vs isinstance()

Which statement is true about type() and isinstance() in Python?

A Both type() and isinstance() behave exactly the same for all objects.

B type() returns True if an object is an instance of a class or its subclasses, isinstance() returns exact type only.

C type() returns the exact type of an object, while isinstance() returns True for an object and its subclasses.

D type() can check multiple types at once, isinstance() cannot.

💡 Hint

Think about inheritance and how these functions treat subclasses.

type() returns the exact type of an object. isinstance() returns True if the object is an instance of the class or any subclass, making it more flexible for inheritance checks.