Dictionary keys, values, and items in Python - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to get all keys from the dictionary.

Python

my_dict = {'a': 1, 'b': 2, 'c': 3}
keys = my_dict.[1]()
print(keys)

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

Avalues

Bkeys

Citems

Dget

Attempts:

3 left

💡 Hint

Common Mistakes

Using values() instead of keys()

Using items() which returns key-value pairs

Trying to access keys as an attribute without parentheses

The keys() method returns all the keys in a dictionary.

2fill in blank

medium

Complete the code to get all values from the dictionary.

Python

my_dict = {'x': 10, 'y': 20, 'z': 30}
vals = my_dict.[1]()
print(vals)

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

Avalues

Bitems

Cpop

Dkeys

Attempts:

3 left

💡 Hint

Common Mistakes

Using keys() instead of values()

Using items() which returns key-value pairs

Trying to pop a value without a key

The values() method returns all the values in a dictionary.

3fill in blank

hard

Fix the error in the code to get all key-value pairs from the dictionary.

Python

data = {'name': 'Alice', 'age': 25}
pairs = data.[1]()
print(pairs)

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

Akeys

Bvalues

Cget

Ditems

Attempts:

3 left

💡 Hint

Common Mistakes

Using keys() or values() which return only one part

Using get() which requires a key argument

The items() method returns all key-value pairs as tuples.

4fill in blank

hard

Fill both blanks to create a dictionary of word lengths for words longer than 3 letters.

Python

words = ['apple', 'bat', 'carrot', 'dog']
lengths = {word: [1](word) for word in words if len(word) [2] 3}
print(lengths)

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

Alen

B>

C<

Dupper()

Attempts:

3 left

💡 Hint

Common Mistakes

Using word instead of len(word) for length

Using less than symbol instead of greater than

Use len(word) to get the length of each word and filter words with length greater than 3 using >.

5fill in blank

hard

Fill all three blanks to create a dictionary with uppercase keys and values greater than 10.

Python

data = {'a': 5, 'b': 15, 'c': 25}
filtered = [1]: [2] for [3], val in data.items() if val > 10}
print(filtered)

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

Ak.upper()

Bval

Ck

Dv

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong variable names like v instead of val or k

Not converting keys to uppercase

Use k.upper() to make keys uppercase, val for values, and k as the key variable in the loop.

Practice

1. Which method would you use to get all the keys from a Python dictionary my_dict?

easy

A. my_dict.values()

B. my_dict.get()

C. my_dict.items()

D. my_dict.keys()

Solution

1. Step 1: Understand dictionary methods

   The keys() method returns all keys in the dictionary.

2. Step 2: Match method to requirement

   Since we want all keys, my_dict.keys() is the correct method.

3. Final Answer:

   my_dict.keys() -> Option D

4. Quick Check:

   keys() = my_dict.keys() [OK]

Hint: Keys come from keys(), values from values(), pairs from items() [OK]

Common Mistakes:

• Confusing keys() with values()
• Using get() which retrieves a single value
• Using items() which returns key-value pairs

2. Which of the following is the correct syntax to get all values from a dictionary data?

easy

A. data.values()

B. data.get_values()

C. data.values

D. values(data)

Solution

1. Step 1: Recall method syntax

   Dictionary methods require parentheses to call them, so values() is correct.

2. Step 2: Check each option

   data.values misses parentheses, get_values() and values(data) are invalid.

3. Final Answer:

   data.values() -> Option A

4. Quick Check:

   values() needs parentheses [OK]

Hint: Always add () to call dictionary methods like values() [OK]

Common Mistakes:

• Forgetting parentheses after method name
• Using non-existent methods like get_values()
• Trying to call values() as a function with dictionary argument

3. What is the output of this code?

my_dict = {'a': 1, 'b': 2}
print(list(my_dict.items()))

medium

A. [('a', 1), ('b', 2)]

B. ['a', 'b']

C. [1, 2]

D. Error

Solution

1. Step 1: Understand items() method

   The items() method returns key-value pairs as tuples.

2. Step 2: Convert items to list

   Using list() converts these pairs into a list of tuples: [('a', 1), ('b', 2)].

3. Final Answer:

   [('a', 1), ('b', 2)] -> Option A

4. Quick Check:

   items() = list of (key, value) pairs [OK]

Hint: items() returns pairs; list() shows them as list of tuples [OK]

Common Mistakes:

• Thinking items() returns only keys or only values
• Expecting a dictionary instead of list of tuples
• Confusing items() with keys() or values()

4. Find the error in this code snippet:

my_dict = {'x': 10, 'y': 20}
for key, value in my_dict.keys():
    print(key, value)

medium

A. Syntax error in for loop

B. keys() returns only keys, cannot unpack into two variables

C. Missing parentheses after print

D. No error, code runs fine

Solution

1. Step 1: Check what keys() returns

   keys() returns only keys, so each item is a single value, not a pair.

2. Step 2: Understand unpacking in for loop

   The loop tries to unpack each key into two variables, causing an error.

3. Final Answer:

   keys() returns only keys, cannot unpack into two variables -> Option B

4. Quick Check:

   keys() = keys only, no pairs [OK]

Hint: keys() gives one value per item; items() gives pairs [OK]

Common Mistakes:

• Trying to unpack keys() into two variables
• Confusing keys() with items()
• Assuming keys() returns key-value pairs

5. You have a dictionary grades = {'Alice': 85, 'Bob': 92, 'Charlie': 78}. Which code snippet correctly prints each student's name and grade using dictionary methods?

hard

A. for name, grade in grades.values():
print(name, grade)

B. for name, grade in grades.keys():
print(name, grade)

C. for name, grade in grades.items():
print(name, grade)

D. for grade in grades.values():
print(grade)

Solution

1. Step 1: Identify method to get pairs

   items() returns key-value pairs, perfect for name and grade.

2. Step 2: Check each option

   for name, grade in grades.values(): print(name, grade) unpacks grades.values() (single values): error. for name, grade in grades.keys(): print(name, grade) unpacks grades.keys() (single keys): error. for grade in grades.values(): print(grade) prints only grades. for name, grade in grades.items(): print(name, grade) correctly unpacks grades.items() pairs.

3. Final Answer:

   for name, grade in grades.items(): print(name, grade) -> Option C

4. Quick Check:

   items() gives key-value pairs for easy unpacking [OK]

Hint: Use items() to loop over keys and values together [OK]

Common Mistakes:

• Using values() when keys and values needed
• Unpacking values() which are single values
• Using keys() without accessing values