Dictionary Methods Quiz

Which method is used to return the value for a specified key if it exists, otherwise returns a default value?

• get()

• keys()

• values()

• items()

Answer explanation

The method 'get()' is used to retrieve the value for a specified key in a dictionary. If the key exists, it returns the corresponding value; if not, it returns a default value, making it the correct choice for this question.

What does the items() method return?

• A view object displaying a list of the dictionary’s key-value pairs

• A shallow copy of the dictionary

• A view object displaying a list of all the values in the dictionary

• A view object displaying a list of all the keys in the dictionary

Answer explanation

The items() method returns a view object that displays a list of the dictionary’s key-value pairs, allowing you to see both keys and their corresponding values together.

Which method updates the dictionary with elements from another dictionary or an iterable of key-value pairs?

• update()

• setdefault()

• pop()

• popitem()

Answer explanation

The correct method is update(). It adds elements from another dictionary or an iterable of key-value pairs to the existing dictionary, modifying it in place.

What does the pop() method do?

• Removes and returns a key-value pair from the dictionary in LIFO order

• Removes all items from the dictionary

• Removes the specified key and returns the corresponding value

• Returns a shallow copy of the dictionary

Answer explanation

The pop() method removes the specified key from a dictionary and returns its corresponding value. This is the correct choice, as it directly describes the method's functionality.

Which method creates a new dictionary with keys from an iterable and values set to a specified value?

• fromkeys()

• update()

• copy()

• clear()

Answer explanation

The method fromkeys() creates a new dictionary by taking an iterable for keys and assigning a specified value to each key. This makes it the correct choice for creating a dictionary with uniform values.

What does the keys() method return?

• A shallow copy of the dictionary

• A view object displaying a list of the dictionary’s key-value pairs

• A view object displaying a list of all the values in the dictionary

• A view object displaying a list of all the keys in the dictionary

Answer explanation

The keys() method returns a view object that displays a list of all the keys in the dictionary. This allows you to see the keys without creating a separate list, making it efficient for accessing dictionary keys.

Which method removes and returns a key-value pair from the dictionary in LIFO order?

• popitem()

• pop()

• clear()

• setdefault()

Answer explanation

The method popitem() removes and returns the last inserted key-value pair from a dictionary, following LIFO (Last In, First Out) order. In contrast, pop() removes a specific key, clear() empties the dictionary, and setdefault() retrieves a value.

What does the values() method return?

• A view object displaying a list of the dictionary’s key-value pairs

• A shallow copy of the dictionary

• A view object displaying a list of all the keys in the dictionary

• A view object displaying a list of all the values in the dictionary

Answer explanation

The values() method returns a view object that displays a list of all the values in the dictionary. This is why the correct answer is 'A view object displaying a list of all the values in the dictionary'.

Which method returns a shallow copy of the dictionary?

• clear()

• copy()

• fromkeys()

• update()

Answer explanation

The method copy() returns a shallow copy of the dictionary, meaning it creates a new dictionary with the same key-value pairs. The other methods do not create a copy: clear() removes items, fromkeys() creates a new dict, and update() modifies the existing one.

What does the setdefault() method do?

• Removes the specified key and returns the corresponding value

• Removes all items from the dictionary

• Returns the value of a specified key, inserting it with a default value if it doesn’t exist

• Removes and returns a key-value pair from the dictionary in LIFO order

Answer explanation

The setdefault() method returns the value of a specified key in a dictionary. If the key does not exist, it inserts the key with a default value and then returns that value, making it useful for initializing dictionary entries.