Why dictionaries are used in Python - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a dictionary with keys as names and values as ages.

Python

ages = {'Alice': 25, 'Bob': 30, 'Charlie': [1]

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

A35

B'35'

C[35]

D(35)

Attempts:

3 left

💡 Hint

Common Mistakes

Putting the number 35 in quotes, making it a string instead of an integer.

The value for 'Charlie' should be an integer representing age, so 35 without quotes is correct.

2fill in blank

medium

Complete the code to access the value for key 'name' in the dictionary.

Python

person = {'name': 'John', 'age': 22}
print(person[1])

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

A['age']

B['name']

C['john']

D['Name']

Attempts:

3 left

💡 Hint

Common Mistakes

Using a wrong key name or wrong case, which causes a KeyError.

To get the value for the key 'name', use person['name'].

3fill in blank

hard

Fix the error in the code to add a new key-value pair to the dictionary.

Python

data = {'x': 10, 'y': 20}
data[1] = 30

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

A['z']

Bappend('z')

Cadd('z')

D.z

Attempts:

3 left

💡 Hint

Common Mistakes

Trying to use list methods like append on a dictionary.

To add a new key 'z' with value 30, use data['z'] = 30.

4fill in blank

hard

Fill both blanks to create a dictionary comprehension that maps numbers to their squares for numbers greater than 2.

Python

squares = {x: x[1]2 for x in range(1, 6) if x [2] 2 }

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

A**

B+

C>

D<

Attempts:

3 left

💡 Hint

Common Mistakes

Using '+' instead of '**' for power, or using '<' instead of '>' for the condition.

The operator for power is '**' and the condition to filter numbers greater than 2 is '>'.

5fill in blank

hard

Fill all three blanks to create a dictionary comprehension that maps uppercase keys to values only if the value is positive.

Python

result = [1]: [2] for k, v in data.items() if v [3] 0 }

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

Ak.upper()

Bv

C>

Dk.lower()

Attempts:

3 left

💡 Hint

Common Mistakes

Using k.lower() instead of k.upper(), or using '<' instead of '>' for filtering.

Use k.upper() for uppercase keys, v for values, and '>' to filter positive values.