type() and isinstance() in Python - Cheat Sheet & Quick Revision

Recall & Review

beginner

What does the type() function do in Python?

The type() function returns the exact type of an object, such as int, str, or list.

beginner

What is the purpose of isinstance() in Python?

<p><code>isinstance()</code> checks if an object is an instance of a class or a subclass, returning <code>True</code> or <code>False</code>.</p>

intermediate

How is type() different from isinstance()?

<p><code>type()</code> checks for the exact type of an object, while <code>isinstance()</code> checks if the object is of a type or any subclass of that type.</p>

intermediate

What will isinstance(5, (int, float)) return and why?

It returns True because 5 is an int, and isinstance() can check against a tuple of types.

intermediate

Can <code>type()</code> be used to check if an object is a subclass instance?

<p>No, <code>type()</code> only checks the exact type, so it does not consider subclass relationships. Use <code>isinstance()</code> for that.</p>

What does type('hello') return?

A hello

B <class 'str'>

C string

D TypeError

type() returns the type of the object, which is str for a string.

Which function checks if an object is an instance of a class or its subclass?

A type()

B instance()

C class()

D isinstance()

isinstance() checks for instance and subclass relationships.

What will type(3.14) == float return?

A False

B 3.14

C True

D TypeError

type() returns the exact type, so this comparison is True.

Which is the correct way to check if obj is either an int or float?

A isinstance(obj, (int, float))

B type(obj) == int or float

C type(obj) in (int, float)

D isinstance(obj, int) and isinstance(obj, float)

isinstance() accepts a tuple of types to check against multiple types.

If class Dog(Animal): pass, what will type(dog) == Animal return if dog is a Dog instance?

A False

B True

C TypeError

D Depends on Python version

type() checks exact type, so it returns False because dog is a Dog, not Animal.

Explain the difference between type() and isinstance() in Python.

Think about how each function treats subclasses.

How can you check if a variable is either an integer or a float using Python built-in functions?

Remember isinstance() can check multiple types at once.