Functions

Learning how to define and call functions, understanding parameters, return values, and scope. Here are 25 questions related to defining and calling functions, understanding parameters, return values,

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1

What is a function in Python?

def greet():
    print("Hello, World!")

greet()

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2

How do you define a function with parameters?

def add(a, b):
    return a + b

result = add(3, 5)
print(result)

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3

What is a default parameter in a function?

def greet(name="Guest"):
    print(f"Hello, {name}!")

greet()
greet("Alice")

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4

How do you define a function with multiple return values?

def get_min_max(numbers):
    return min(numbers), max(numbers)

minimum, maximum = get_min_max([1, 2, 3, 4, 5])
print(minimum, maximum)

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5

What are keyword arguments?

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

display_info(name="John", age=30)

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6

How do you define a function with variable-length arguments?

def print_numbers(*args):
    for number in args:
        print(number)

print_numbers(1, 2, 3, 4, 5)

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7

**What are kwargs in a function definition?

def show_info(**kwargs):
    for key, value in kwargs.items():
        print(f"{key}: {value}")

show_info(name="Alice", age=25, city="New York")

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8

How does variable scope work in Python functions?

def outer_function():
    outer_var = "I am outside!"

    def inner_function():
        inner_var = "I am inside!"
        print(outer_var)

    inner_function()
    # print(inner_var)  # This will cause an error

outer_function()

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9

What is a lambda function?

square = lambda x: x ** 2

print(square(4))

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10

How do you use a function as an argument to another function?

def operate_on_numbers(func, a, b):
    return func(a, b)

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

result = operate_on_numbers(add, 3, 4)
print(result)

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11

How can you call a function inside another function?

def multiply(a, b):
    return a * b

def double_and_multiply(x):
    doubled = x * 2
    return multiply(doubled, 3)

result = double_and_multiply(4)
print(result)

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12

What is the difference between return and print in functions?

def calculate_square(x):
    return x ** 2

def print_square(x):
    print(x ** 2)

print(calculate_square(5))  # Returns the value
print_square(5)  # Prints the value

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13

How do you handle exceptions inside a function?

def safe_divide(a, b):
    try:
        result = a / b
    except ZeroDivisionError:
        return "Cannot divide by zero"
    return result

print(safe_divide(10, 2))
print(safe_divide(10, 0))

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14

What are function annotations?

def greet(name: str, age: int) -> str:
    return f"Hello {name}, you are {age} years old."

print(greet("Alice", 30))

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15

How do you use a function inside a list comprehension?

def square(x):
    return x ** 2

numbers = [1, 2, 3, 4, 5]
squares = [square(x) for x in numbers]
print(squares)

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16

How can you define a function with a nonlocal variable?

def outer_function():
    outer_var = "I am outer"

    def inner_function():
        nonlocal outer_var
        outer_var = "I am modified"
        print(outer_var)

    inner_function()
    print(outer_var)

outer_function()

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17

What is a closure in Python?

def outer_function(x):
    def inner_function(y):
        return x + y
    return inner_function

add_five = outer_function(5)
print(add_five(3))

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18

How do you use a function as a callback?

def process_data(data, callback):
    result = callback(data)
    return result

def add_ten(value):
    return value + 10

print(process_data(5, add_ten))

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19

How can you pass a function as an argument with *args or **kwargs?

def print_info(*args, **kwargs):
    print("Arguments:", args)
    print("Keyword Arguments:", kwargs)

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

print_info(1, 2, 3, a=4, b=5)

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20

How do you create a recursive function?

def factorial(n):
    if n == 0:
        return 1
    else:
        return n * factorial(n - 1)

print(factorial(5))

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21

What is a higher-order function?

def higher_order_function(func, value):
    return func(value)

def square(x):
    return x ** 2

print(higher_order_function(square, 4))

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22

How do you ensure a function’s execution time?

import time

def timed_function():
    start_time = time.time()
    # Code to time
    time.sleep(2)
    end_time = time.time()
    print(f"Execution time: {end_time - start_time} seconds")

timed_function()

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23

What is a function decorator?

def decorator_func(func):
    def wrapper():
        print("Something is happening before the function is called.")
        func()
        print("Something is happening after the function is called.")
    return wrapper

@decorator_func
def say_hello():
    print("Hello!")

say_hello()

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24

How do you use function overloading in Python?

from typing import Union

def greet(name: str) -> str:
    return f"Hello, {name}!"

def greet(name: str, age: Union[int, None] = None) -> str:
    if age:
        return f"Hello, {name}. You are {age} years old."
    return f"Hello, {name}!"

print(greet("Alice"))
print(greet("Alice", 30))

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25

How do you use a function’s docstring?

def add(a, b):
    """
    Add two numbers together.

    Parameters:
    a (int or float): The first number.
    b (int or float): The second number.

    Returns:
    int or float: The sum of a and b.
    """
    return a + b

print(add.__doc__)

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