Keyword arguments in Python - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

Output of function call with keyword arguments

What is the output of this Python code?

Python

def greet(name, greeting="Hello", punctuation="!"):
    return f"{greeting}, {name}{punctuation}"

print(greet(name="Alice", punctuation=".", greeting="Hi"))

A "Hi, Alice!"

B "Hello, Alice!"

C "Hi, Alice."

D "Hello, Alice."

💡 Hint

Check how keyword arguments match the function parameters regardless of order.

The function greet is called with keyword arguments. The greeting is set to "Hi", punctuation to ".", and name to "Alice". The output string uses these values exactly.

❓ Predict Output

intermediate

Function call with missing keyword argument

What is the output of this code snippet?

Python

def calculate_area(length, width=5):
    return length * width

print(calculate_area(width=3, length=4))

A 20

B 12

C TypeError

D 15

💡 Hint

Keyword arguments can be passed in any order, but all required arguments must be provided.

The function is called with length=4 and width=3. The area is 4 * 3 = 12.

❓ Predict Output

advanced

Output when mixing positional and keyword arguments

What will this code print?

Python

def describe_pet(pet_name, animal_type="dog"):
    return f"I have a {animal_type} named {pet_name}."

print(describe_pet("Whiskers", animal_type="cat"))

A TypeError

B "I have a dog named Whiskers."

C "I have a cat named animal_type."

D "I have a cat named Whiskers."

💡 Hint

Positional arguments come first, then keyword arguments can override defaults.

The first argument "Whiskers" is assigned to pet_name. The keyword argument animal_type="cat" overrides the default "dog". So the output uses "cat" and "Whiskers".

❓ Predict Output

advanced

Error caused by duplicate argument assignment

What error does this code raise?

Python

def multiply(x, y):
    return x * y

print(multiply(2, x=3))

A TypeError: multiply() got multiple values for argument 'x'

B TypeError: multiply() missing 1 required positional argument: 'y'

C SyntaxError

D 6

💡 Hint

Check if the same argument is given twice by position and keyword.

The first argument 2 is assigned to x positionally, then x=3 is passed as keyword argument. This causes a conflict and raises a TypeError about multiple values for 'x'.

🧠 Conceptual

expert

Understanding **kwargs behavior

What is the output of this code?

Python

def show_info(**kwargs):
    return kwargs.get('name', 'Unknown') + ' is ' + str(kwargs.get('age', 'ageless'))

print(show_info(age=30, name='Bob'))

A "Bob is 30"

B TypeError

C "Bob is ageless"

D "Unknown is 30"

💡 Hint

**kwargs collects keyword arguments into a dictionary.

The function receives keyword arguments as a dictionary. It gets 'name' and 'age' keys and returns a string combining them. Since both keys are provided, it returns "Bob is 30".

Practice

1. What is the main advantage of using keyword arguments when calling a function in Python?

easy

A. Keyword arguments make the function run faster.

B. You must provide arguments in the exact order defined in the function.

C. You can specify arguments by name, making the code clearer.

D. They allow you to skip required arguments.

Solution

1. Step 1: Understand keyword arguments

   Keyword arguments let you name the inputs when calling a function, so you don't have to remember the order.

2. Step 2: Compare options

   You can specify arguments by name, making the code clearer. correctly states that naming arguments makes code clearer. Options B, C, and D are incorrect because keyword arguments do not require order, do not affect speed, and cannot skip required arguments.

3. Final Answer:

   You can specify arguments by name, making the code clearer. -> Option C

4. Quick Check:

   Keyword arguments = clearer code [OK]

Hint: Keyword arguments name inputs, so order doesn't matter [OK]

Common Mistakes:

• Thinking keyword arguments must follow positional order
• Believing keyword arguments speed up the function
• Assuming keyword arguments can skip required parameters

2. Which of the following is the correct way to call the function def greet(name, age): using keyword arguments?

easy

A. greet(name='Alice', age=30)

B. greet('Alice', 30)

C. greet(age=30, 'Alice')

D. greet(name=30, age='Alice')

Solution

1. Step 1: Check keyword argument syntax

   Keyword arguments require the format parameter=value. greet(name='Alice', age=30) uses name='Alice' and age=30, which is correct.

2. Step 2: Identify errors in other options

   greet('Alice', 30) uses positional arguments only, which is valid syntax but does not use keyword arguments. greet(age=30, 'Alice') places positional argument after keyword, which is invalid syntax. greet(name=30, age='Alice') swaps types incorrectly.

3. Final Answer:

   greet(name='Alice', age=30) -> Option A

4. Quick Check:

   Keyword args = parameter=value pairs [OK]

Hint: Use parameter=value pairs for keyword arguments [OK]

Common Mistakes:

• Placing positional arguments after keyword arguments
• Swapping argument names and values
• Mixing types incorrectly in keyword arguments

3. What will be the output of the following code?

def info(name, age):
    print(f"Name: {name}, Age: {age}")

info(age=25, name='Bob')

medium

A. Name: 25, Age: Bob

B. Name: Bob, Age: 25

C. Name: , Age:

D. TypeError

Solution

1. Step 1: Understand keyword argument order

   Keyword arguments allow passing arguments in any order by naming them explicitly.

2. Step 2: Match arguments to parameters

   Here, age=25 and name='Bob' are passed, so name gets 'Bob' and age gets 25.

3. Final Answer:

   Name: Bob, Age: 25 -> Option B

4. Quick Check:

   Keyword args reorder inputs correctly [OK]

Hint: Keyword arguments can be in any order [OK]

Common Mistakes:

• Assuming order matters with keyword arguments
• Confusing parameter names with values
• Expecting errors when order is changed

4. Identify the error in the following function call:

def multiply(x, y):
    return x * y

result = multiply(x=5, 10)

medium

A. SyntaxError: positional argument after keyword argument

B. TypeError: missing required positional argument

C. No error, result is 50

D. NameError: variable not defined

Solution

1. Step 1: Check argument order rules

   In Python, positional arguments cannot come after keyword arguments in a function call.

2. Step 2: Analyze the call

   The call multiply(x=5, 10) has a keyword argument first, then a positional argument, which causes a syntax error.

3. Final Answer:

   SyntaxError: positional argument after keyword argument -> Option A

4. Quick Check:

   Positional args must come before keyword args [OK]

Hint: Positional arguments must come before keyword arguments [OK]

Common Mistakes:

• Placing positional arguments after keyword arguments
• Confusing error types for this syntax
• Assuming this call runs without error

5. Given the function def order(item, quantity=1, price=10):, which call correctly orders 3 items with a price of 15 each using keyword arguments?

hard

A. order('apple', 3, 15)

B. order(price=15, quantity=3)

C. order(quantity=3, 'apple', price=15)

D. order(item='apple', price=15, quantity=3)

Solution

1. Step 1: Understand function parameters and defaults

   The function has one required parameter item and two optional parameters quantity and price with defaults.

2. Step 2: Check each call for correctness

   order('apple', 3, 15) uses positional arguments only, which is valid but not keyword arguments. order(item='apple', price=15, quantity=3) uses keyword arguments for all parameters, correctly naming them in any order. order(quantity=3, 'apple', price=15) places positional argument after keyword argument, which is invalid. order(price=15, quantity=3) misses the required item argument.

3. Final Answer:

   order(item='apple', price=15, quantity=3) -> Option D

4. Quick Check:

   Keyword args can be in any order, all required given [OK]

Hint: Use all required keywords, order doesn't matter [OK]

Common Mistakes:

• Omitting required arguments
• Placing positional after keyword arguments
• Using positional only when keyword is asked