User authentication basics in Raspberry Pi - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to check if the entered password matches the stored password.

Raspberry Pi

if entered_password [1] stored_password:
    print("Access granted")
else:
    print("Access denied")

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

A<

B!=

C==

D>

Attempts:

3 left

💡 Hint

Common Mistakes

Using assignment operator '=' instead of comparison '=='.

We use == to compare if two passwords are the same.

2fill in blank

medium

Complete the code to ask the user for their username.

Raspberry Pi

username = input([1])

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

A"Enter your username: "

B'Enter your email: '

C'Enter your password: '

D"Enter your PIN: "

Attempts:

3 left

💡 Hint

Common Mistakes

Using the wrong prompt message that asks for password or PIN.

The prompt should ask for the username, so the message is "Enter your username: ".

3fill in blank

hard

Fix the error in the code to securely check the password using hashing.

Raspberry Pi

import hashlib

hashed_input = hashlib.sha256(entered_password.encode()).hexdigest()
if hashed_input [1] stored_hashed_password:
    print("Access granted")
else:
    print("Access denied")

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

A=

B==

Cis

D!=

Attempts:

3 left

💡 Hint

Common Mistakes

Using '=' which assigns instead of compares.

Using 'is' which checks identity, not equality.

To compare hashed passwords, use == to check equality.

4fill in blank

hard

Fill both blanks to create a dictionary comprehension that stores usernames and their hashed passwords only if the password length is greater than 5.

Raspberry Pi

user_hashes = {user: hashlib.sha256([1].encode()).hexdigest() for user, [2] in users.items() if len(password) > 5}

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

Apassword

Bpassw

Cpwd

Dpasswd

Attempts:

3 left

💡 Hint

Common Mistakes

Using different variable names that are not defined in the loop.

Both blanks refer to the password variable, which is named 'password' in the loop.

5fill in blank

hard

Fill all three blanks to create a function that checks if a username exists and the password matches the stored hash.

Raspberry Pi

def authenticate([1], [2]):
    if [1] in user_db and hashlib.sha256([2].encode()).hexdigest() == user_db[[1]]:
        return True
    return False

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

Ausername

Bpassword

Duser

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing variable names or using undefined variables.

The function takes username and password as parameters. The username is checked in the database and used to get the stored hash.