Function definition and syntax in Python - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to define a function named greet.

Python

def [1]():
    print("Hello!")

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

Agreet

Bhello

Csay_hello

Dprint_greet

Attempts:

3 left

💡 Hint

Common Mistakes

Using a different function name than 'greet'.

Forgetting the parentheses after the function name.

The function name should be greet as specified.

2fill in blank

medium

Complete the code to define a function that takes one parameter named name.

Python

def greet([1]):
    print(f"Hello, {name}!")

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

Aperson

Binput

Cuser

Dname

Attempts:

3 left

💡 Hint

Common Mistakes

Using a different parameter name than 'name'.

Forgetting to include the parameter in parentheses.

The parameter should be named name to match the print statement.

3fill in blank

hard

Fix the error in the function definition by completing the code.

Python

def add_numbers(a, b[1]:
    return a + b

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

A,

B:

C)

D]

Attempts:

3 left

💡 Hint

Common Mistakes

Using a colon instead of a closing parenthesis.

Leaving the parentheses unclosed.

The function parameters must be enclosed in parentheses. The missing closing parenthesis ) fixes the syntax error.

4fill in blank

hard

Fill both blanks to define a function named multiply that returns the product of two parameters x and y.

Python

def [1]([2], y):
    return x * y

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

Amultiply

Bx

Cproduct

Dz

Attempts:

3 left

💡 Hint

Common Mistakes

Using a different function name than 'multiply'.

Using a parameter name that does not match the return statement.

The function name should be multiply and the first parameter should be x to match the return statement.

5fill in blank

hard

Fill all three blanks to define a function named is_even that returns True if a number n is even, otherwise False.

Python

def [1]([2]):
    if n [3] 2 == 0:
        return True
    else:
        return False

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

Ais_even

Bn

C%

D==

Attempts:

3 left

💡 Hint

Common Mistakes

Using the wrong operator instead of modulo.

Using a different parameter name than 'n'.

Using a different function name.

The function name is is_even, the parameter is n, and the modulo operator % checks if the number is divisible by 2.

Practice

1. What keyword do you use to start defining a function in Python?

easy

A. function

B. define

C. func

D. def

Solution

1. Step 1: Recall Python function syntax

   In Python, functions are defined using the keyword def.

2. Step 2: Compare options

   Only def uses the correct keyword def. Others are not valid Python keywords.

3. Final Answer:

   def -> Option D

4. Quick Check:

   Function definition starts with def [OK]

Hint: Remember: def starts every function in Python [OK]

Common Mistakes:

• Using 'function' instead of 'def'
• Using 'func' or 'define' which are not Python keywords

2. Which of the following is the correct syntax to define a function named greet that takes no parameters?

easy

A. def greet():

B. function greet():

C. def greet[]:

D. def greet:

Solution

1. Step 1: Check function header syntax

   The correct syntax uses def, function name, parentheses for parameters, and a colon.

2. Step 2: Validate each option

   def greet(): matches this exactly: def greet():. Others have wrong keywords, brackets, or missing parentheses.

3. Final Answer:

   def greet(): -> Option A

4. Quick Check:

   def + name + () + : is correct syntax [OK]

Hint: Function name + () + : after def is always needed [OK]

Common Mistakes:

• Omitting parentheses after function name
• Using square brackets instead of parentheses
• Using 'function' keyword instead of 'def'

3. What will be the output of this code?

def add(x, y):
    return x + y

print(add(3, 4))

medium

A. 7

B. 34

C. TypeError

D. None

Solution

1. Step 1: Understand function behavior

   The function add takes two numbers and returns their sum.

2. Step 2: Calculate the return value

   Calling add(3, 4) returns 3 + 4 = 7, which is printed.

3. Final Answer:

   7 -> Option A

4. Quick Check:

   3 + 4 = 7 [OK]

Hint: Return sends back the sum; print shows it [OK]

Common Mistakes:

• Concatenating numbers as strings (getting '34')
• Forgetting to return value (getting None)
• Passing wrong number of arguments causing TypeError

4. Find the error in this function definition:

def multiply(a, b)
    return a * b

medium

A. Indentation error in return statement

B. Missing colon at the end of function header

C. Wrong function name

D. Parameters should be in square brackets

Solution

1. Step 1: Check function header syntax

   The function header must end with a colon (:).

2. Step 2: Identify missing colon

   The code misses the colon after def multiply(a, b), causing a syntax error.

3. Final Answer:

   Missing colon at the end of function header -> Option B

4. Quick Check:

   Function header must end with : [OK]

Hint: Always put : after function header line [OK]

Common Mistakes:

• Forgetting colon after function header
• Incorrect indentation of return line
• Using wrong brackets for parameters

5. You want to write a function is_even that returns True if a number is even, otherwise False. Which is the correct function?

hard

A. def is_even(n):
return n % 2

B. def is_even(n):
return n / 2 == 0

C. def is_even(n):
if n % 2 == 0:
return True
else:
return False

D. def is_even(n):
if n % 2:
return True
else:
return False

Solution

1. Step 1: Understand even number check

   A number is even if remainder when divided by 2 is zero (n % 2 == 0).

2. Step 2: Evaluate each option

   def is_even(n): if n % 2 == 0: return True else: return False correctly returns True if remainder is zero, else False. def is_even(n): return n / 2 == 0 uses division instead of modulo. def is_even(n): if n % 2: return True else: return False returns True when remainder is non-zero (odd). def is_even(n): return n % 2 returns remainder directly (not boolean).

3. Final Answer:

   def is_even(n): if n % 2 == 0: return True else: return False -> Option C

4. Quick Check:

   Use modulo == 0 to check even [OK]

Hint: Use n % 2 == 0 to check even numbers [OK]

Common Mistakes:

• Using division instead of modulo
• Returning remainder instead of boolean
• Confusing condition for even check