Dictionaries and key-value pairs in Intro to Computing - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a dictionary with a key 'name' and value 'Alice'.

Intro to Computing

person = [1]

Drag options to blanks, or click blank then click option'

A{'name': 'Alice'}

B['name', 'Alice']

C('name', 'Alice')

D'name': 'Alice'

Attempts:

3 left

💡 Hint

Common Mistakes

Using square brackets [] creates a list, not a dictionary.

Using parentheses () creates a tuple, not a dictionary.

Writing key-value without braces is invalid syntax.

The correct way to create a dictionary is using curly braces with key-value pairs inside, like {'name': 'Alice'}.

2fill in blank

medium

Complete the code to access the value of the key 'age' from the dictionary.

Intro to Computing

age = person[1]

Drag options to blanks, or click blank then click option'

A.age

B(age)

C['age']

D{'age'}

Attempts:

3 left

💡 Hint

Common Mistakes

Using parentheses () tries to call a function, which is wrong here.

Using dot notation works for objects but not dictionaries.

Using curly braces {} is for creating dictionaries, not accessing values.

To get a value from a dictionary, use square brackets with the key as a string, like person['age'].

3fill in blank

hard

Fix the error in the code to add a new key 'city' with value 'Paris' to the dictionary.

Intro to Computing

person[1] = 'Paris'

Drag options to blanks, or click blank then click option'

A.city

B['city']

C(city)

D{city}

Attempts:

3 left

💡 Hint

Common Mistakes

Using dot notation tries to access an attribute, which dictionaries don't support.

Using parentheses () or curly braces {} is invalid syntax here.

To add or update a key-value pair in a dictionary, use square brackets with the key as a string, like person['city'] = 'Paris'.

4fill in blank

hard

Complete the code to create a dictionary comprehension that maps each word to its length for words longer than 3 letters.

Intro to Computing

{word: len(word) for word in words if len(word) [1] 3}

Drag options to blanks, or click blank then click option'

A:

B>

C<

D=

Attempts:

3 left

💡 Hint

Common Mistakes

Using '=' instead of ':' causes syntax errors.

Using '<' instead of '>' changes the filter condition incorrectly.

In dictionary comprehensions, use a colon ':' to separate keys and values. The condition checks if the word length is greater than 3 using '>'.

5fill in blank

hard

Fill all three blanks to create a dictionary from a list of tuples, where keys are names in uppercase and values are ages greater than 20.

Intro to Computing

result = [1]: [2] for name, age in data if age [3] 20}

Drag options to blanks, or click blank then click option'

Aname.upper()

Bage

C>

Dname.lower()

Attempts:

3 left

💡 Hint

Common Mistakes

Using name.lower() instead of uppercase changes keys incorrectly.

Using = instead of > causes syntax errors.

Swapping keys and values causes wrong dictionary structure.

The key is the uppercase name using name.upper(), the value is age, and the condition filters ages greater than 20 using >.