recap

NSFW

Python Make-Up Exam Final Recap / Cheat Sheet

This guide covers the exact style of problems from the midterm:

BMI category
Student grade
Number guessing game
Shopping cart
Password validator bonus

It also includes the main patterns that can appear in similar make-up problems.

0. General Exam Strategy

Most problems follow this structure:

def function_name():
    # 1. Ask for input

    # 2. Validate input if needed

    # 3. Do calculation / logic

    # 4. Use if / elif / else

    # 5. return or print result

At the end, run the function:

print(function_name())

or:

function_name()

Use print(...) when the task says display / print.
Use return ... when the task says return.

1. Basic Python Things You Must Know

Input

name = input("Enter name: ")

Important: input() always gives a string.

So if user types:

Python stores it as:

"25"

not:

For numbers, convert it.

Integer:

age = int(input("Enter age: "))

Decimal number:

height = float(input("Enter height: "))

Use int() for whole numbers.
Use float() for decimal numbers.

2. Print and f-strings

Normal print:

print("Hello")

Print variable:

name = "Giorgi"
print("Hello", name)

f-string:

name = "Giorgi"
print(f"Hello, {name}")

Another example:

total = 29.6
print(f"Total: {total:.2f}")

Output:

Total: 29.60

:.2f means show 2 digits after decimal point.

3. If / Elif / Else

Use this when there are categories.

if condition:
    ...
elif condition:
    ...
else:
    ...

Example:

score = 85

if score >= 91:
    grade = "A"
elif score >= 81:
    grade = "B"
elif score >= 71:
    grade = "C"
else:
    grade = "F"

Important rule:

When using >=, usually go from biggest to smallest.

if score >= 91:
elif score >= 81:
elif score >= 71:

When using <, usually go from smallest to biggest.

if bmi < 18.5:
elif bmi < 25:
elif bmi < 30:
else:

4. Try / Except for Validation

Use this when user must enter a number.

try:
    number = int(input("Enter number: "))
except ValueError:
    print("Invalid number")

If user enters:

hello

then int("hello") fails, but your program does not crash.

For decimal:

try:
    weight = float(input("Enter weight: "))
except ValueError:
    print("Invalid number")

5. While True

Use this when you want to keep asking until input is correct.

while True:
    answer = input("Type done: ")

    if answer == "done":
        break

break stops the loop.

Example for valid positive number:

while True:
    try:
        number = float(input("Enter positive number: "))

        if number <= 0:
            print("Number must be greater than 0.")
        else:
            break

    except ValueError:
        print("Please enter a valid number.")

6. Lists

Create list:

cart = []

Add item:

cart.append("Apple")

Remove item:

cart.remove("Apple")

Check if item exists:

if "Apple" in cart:
    cart.remove("Apple")

Loop through list:

for item in cart:
    print(item)

Sorted list:

for item in sorted(cart):
    print(item)

7. Dictionaries

Dictionary stores key-value pairs.

prices = {
    "Apple": 2.7,
    "Cola": 4.5
}

Get price:

prices["Apple"]

Output:

2.7

Check if item exists in dictionary:

if item in prices:
    print(prices[item])
else:
    print("Item not found")

8. Split Input

If user enters numbers in one line:

20 30 40

Use:

scores = input("Enter scores: ").split()

This gives:

["20", "30", "40"]

They are still strings.

Convert to integers:

scores = [int(score) for score in scores]

Short version:

scores = [int(score) for score in input("Enter scores: ").split()]

Then:

total = sum(scores)

9. Important List Comprehension

This:

scores = [int(score) for score in scores]

means:

Go through every item in scores, convert it to integer, and make a new list.

Example:

Before:

scores = ["20", "30", "40"]

After:

scores = [20, 30, 40]

Long version:

new_scores = []

for score in scores:
    new_scores.append(int(score))

scores = new_scores

10. String Methods

text.lower()

makes lowercase.

"ADD".lower()

becomes:

"add"


text.title()

makes title case.

"apple".title()

becomes:

"Apple"


text.strip()

removes spaces from beginning and end.

"  add apple  ".strip()

becomes:

"add apple"


text.split()

splits by spaces.

"add apple".split()

gives:

["add", "apple"]

11. Problem 1 — BMI Category

Task

Create function bmi_category().

Ask for:

name
weight in kg
height in meters

Calculate:

BMI = weight / height²

In Python:

bmi = weight / (height ** 2)

Categories:

Underweight: BMI < 18.5
Normal weight: 18.5 <= BMI < 25
Overweight: 25 <= BMI < 30
Obese: BMI >= 30

Return dictionary:

{"name": name, "category": category}

Perfect Solution

def bmi_category():
    name = input("Enter your name: ")

    while True:
        try:
            weight = float(input("Enter your weight in kg: "))

            if weight <= 0:
                print("Weight must be greater than 0.")
            else:
                break

        except ValueError:
            print("Please enter a valid number for weight.")

    while True:
        try:
            height = float(input("Enter your height in meters: "))

            if height <= 0:
                print("Height must be greater than 0.")
            else:
                break

        except ValueError:
            print("Please enter a valid number for height.")

    bmi = weight / (height ** 2)

    if bmi < 18.5:
        category = "Underweight"
    elif bmi < 25:
        category = "Normal weight"
    elif bmi < 30:
        category = "Overweight"
    else:
        category = "Obese"

    return {"name": name, "category": category}


print(bmi_category())

What to remember

bmi = weight / (height ** 2)

Use float() because weight and height can be decimals.

Use this category pattern:

if bmi < 18.5:
    category = "Underweight"
elif bmi < 25:
    category = "Normal weight"
elif bmi < 30:
    category = "Overweight"
else:
    category = "Obese"

You do not need to write:

elif bmi >= 18.5 and bmi < 25:

because if Python reaches that line, it already knows BMI was not below 18.5.

12. Similar BMI-Style Problems

This problem type means:

input number → calculate → category → return dictionary

Similar examples:

Age Category

def age_category():
    name = input("Enter name: ")

    age = int(input("Enter age: "))

    if age < 13:
        category = "Child"
    elif age < 20:
        category = "Teenager"
    elif age < 65:
        category = "Adult"
    else:
        category = "Senior"

    return {"name": name, "category": category}


print(age_category())

Temperature Category

def temperature_category():
    temperature = float(input("Enter temperature: "))

    if temperature < 0:
        category = "Freezing"
    elif temperature < 15:
        category = "Cold"
    elif temperature < 25:
        category = "Warm"
    else:
        category = "Hot"

    return {"category": category}


print(temperature_category())

13. Problem 2 — Student Grade

Task

Create function calculate_grade().

Ask:

student name
scores in one input, separated by spaces

Example input:

30 25 28

Find sum:

total_score = sum(scores)

Grading:

A: 91–100
B: 81–90
C: 71–80
D: 61–70
E: 51–60
F: below 51

Return:

{"name": name, "grade": grade}

Perfect Solution

def calculate_grade():
    name = input("Enter student's name: ")

    while True:
        try:
            scores = [int(score) for score in input("Enter scores separated by spaces: ").split()]

            if len(scores) == 0:
                print("Please enter at least one score.")
            elif any(score < 0 for score in scores):
                print("Scores cannot be negative.")
            elif sum(scores) > 100:
                print("Total score cannot be greater than 100.")
            else:
                break

        except ValueError:
            print("Please enter only integer numbers separated by spaces.")

    total_score = sum(scores)

    if total_score >= 91:
        grade = "A"
    elif total_score >= 81:
        grade = "B"
    elif total_score >= 71:
        grade = "C"
    elif total_score >= 61:
        grade = "D"
    elif total_score >= 51:
        grade = "E"
    else:
        grade = "F"

    return {"name": name, "grade": grade}


print(calculate_grade())

Important line

scores = [int(score) for score in input("Enter scores separated by spaces: ").split()]

Meaning:

User enters "30 25 28"
.split() makes ["30", "25", "28"]
int(score) converts to [30, 25, 28]

Then:

total_score = sum(scores)

Grade logic

Use >= from highest to lowest:

if total_score >= 91:
    grade = "A"
elif total_score >= 81:
    grade = "B"
elif total_score >= 71:
    grade = "C"
elif total_score >= 61:
    grade = "D"
elif total_score >= 51:
    grade = "E"
else:
    grade = "F"

Do not start from 51, because then 95 would also be greater than 51 and get wrong grade.

14. Similar Student Grade Problems

Average Grade

Instead of sum:

average = sum(scores) / len(scores)

Code:

def calculate_average_grade():
    name = input("Enter student's name: ")

    try:
        scores = [int(score) for score in input("Enter scores: ").split()]

        if len(scores) == 0:
            return "Invalid input"

        average = sum(scores) / len(scores)

        if average >= 91:
            grade = "A"
        elif average >= 81:
            grade = "B"
        elif average >= 71:
            grade = "C"
        elif average >= 61:
            grade = "D"
        elif average >= 51:
            grade = "E"
        else:
            grade = "F"

        return {"name": name, "grade": grade}

    except ValueError:
        return "Invalid input"


print(calculate_average_grade())

Pass / Fail

def pass_fail():
    name = input("Enter student's name: ")

    try:
        scores = [int(score) for score in input("Enter scores: ").split()]
        total = sum(scores)

        if total >= 51:
            result = "Pass"
        else:
            result = "Fail"

        return {"name": name, "result": result}

    except ValueError:
        return "Invalid input"


print(pass_fail())

Highest Score

def highest_score():
    scores = [int(score) for score in input("Enter scores: ").split()]
    return max(scores)


print(highest_score())

Lowest Score

def lowest_score():
    scores = [int(score) for score in input("Enter scores: ").split()]
    return min(scores)


print(lowest_score())

Count Passing Scores

def count_passing_scores():
    scores = [int(score) for score in input("Enter scores: ").split()]

    count = 0

    for score in scores:
        if score >= 51:
            count += 1

    return count


print(count_passing_scores())

15. Problem 3 — Number Guessing Game

Task

Create function guess().

Difficulty:

Easy: 1–50, 10 guesses
Hard: 1–100, 7 guesses

Use random number.

After each guess, print:

Too high
Too low
Correct

Show guesses remaining.

If user runs out, reveal number.

Reject:

non-integers
out-of-range guesses

Perfect Solution

import random

def guess():
    while True:
        difficulty = input("Choose difficulty: easy or hard: ").lower()

        if difficulty == "easy":
            max_number = 50
            attempts = 10
            break
        elif difficulty == "hard":
            max_number = 100
            attempts = 7
            break
        else:
            print("Invalid difficulty. Please choose easy or hard.")

    secret_number = random.randint(1, max_number)

    print("I chose a number between 1 and", max_number)

    while attempts > 0:
        try:
            user_guess = int(input("Enter your guess: "))

            if user_guess < 1 or user_guess > max_number:
                print("Invalid guess. Enter a number between 1 and", max_number)
                continue

            attempts -= 1

            if user_guess == secret_number:
                print("Correct!")
                return

            elif user_guess > secret_number:
                print("Too high!")

            else:
                print("Too low!")

            print("Guesses remaining:", attempts)

        except ValueError:
            print("Please enter an integer number.")

    print("You ran out of guesses. The number was", secret_number)


guess()

Important things

Import random:

import random

Generate number:

secret_number = random.randint(1, max_number)

random.randint(1, 50) includes both 1 and 50.

Attempts loop:

while attempts > 0:

Subtract one attempt after a valid guess:

attempts -= 1

Correct answer stops the function:

if user_guess == secret_number:
    print("Correct!")
    return

Out-of-range guess should not count:

if user_guess < 1 or user_guess > max_number:
    print("Invalid guess")
    continue

continue means skip rest of loop and ask again.

16. Similar Guessing Game Problems

Dice Guessing Game

import random

def dice_guess():
    secret_number = random.randint(1, 6)
    attempts = 3

    while attempts > 0:
        try:
            user_guess = int(input("Guess number from 1 to 6: "))

            if user_guess < 1 or user_guess > 6:
                print("Enter number between 1 and 6.")
                continue

            attempts -= 1

            if user_guess == secret_number:
                print("Correct!")
                return
            else:
                print("Wrong!")
                print("Attempts left:", attempts)

        except ValueError:
            print("Enter an integer.")

    print("You lost. The number was", secret_number)


dice_guess()

PIN Guessing Game

import random

def pin_game():
    pin = random.randint(1000, 9999)
    attempts = 5

    while attempts > 0:
        try:
            guess = int(input("Enter 4-digit PIN: "))

            if guess < 1000 or guess > 9999:
                print("PIN must be 4 digits.")
                continue

            attempts -= 1

            if guess == pin:
                print("Correct PIN!")
                return
            else:
                print("Wrong PIN.")
                print("Attempts left:", attempts)

        except ValueError:
            print("Enter only integers.")

    print("You failed. The PIN was", pin)


pin_game()

Random Math Quiz

import random

def math_quiz():
    a = random.randint(1, 20)
    b = random.randint(1, 20)
    correct_answer = a + b

    attempts = 3

    print("What is", a, "+", b, "?")

    while attempts > 0:
        try:
            answer = int(input("Enter answer: "))

            attempts -= 1

            if answer == correct_answer:
                print("Correct!")
                return
            else:
                print("Wrong.")
                print("Attempts left:", attempts)

        except ValueError:
            print("Enter an integer.")

    print("You lost. Correct answer was", correct_answer)


math_quiz()

Random Word Guess

import random

def word_guess():
    words = ["apple", "banana", "cherry"]
    secret_word = random.choice(words)

    attempts = 3

    while attempts > 0:
        guess = input("Guess word: ").lower()

        attempts -= 1

        if guess == secret_word:
            print("Correct!")
            return
        else:
            print("Wrong!")
            print("Attempts left:", attempts)

    print("You lost. The word was", secret_word)


word_guess()

Use:

random.randint(1, 100)

for random numbers.

Use:

random.choice(words)

for random item from a list.

17. Problem 4 — Shopping Cart

Task

Create function shopping_cart().

Use dictionary:

{
    "Apple": 2.7,
    "Orange": 3.5,
    "Cola": 4.5,
    "Mascarpone": 14.9,
    "Beef": 22.4,
    "Pork": 18.9,
    "Nutella": 27.5
}

Start with empty list:

cart = []

Commands:

add apple
remove apple
show
done

show displays all items sorted alphabetically and total.

done shows final total and exits.

Ignore case:

ADD apple
Add Apple
add apple

should all work.

Perfect Simple Solution

def shopping_cart():
    prices = {
        "Apple": 2.7,
        "Orange": 3.5,
        "Cola": 4.5,
        "Mascarpone": 14.9,
        "Beef": 22.4,
        "Pork": 18.9,
        "Nutella": 27.5
    }

    cart = []

    while True:
        user_input = input("Enter command: ").strip()

        if user_input.lower() == "show":
            total = 0

            print("Shopping cart:")

            for item in sorted(cart):
                price = prices[item]
                total += price
                print(f"{item}: {price}")

            print(f"Total: {total:.2f}")

        elif user_input.lower() == "done":
            total = 0

            print("Shopping cart:")

            for item in sorted(cart):
                price = prices[item]
                total += price
                print(f"{item}: {price}")

            print(f"Total: {total:.2f}")
            break

        else:
            parts = user_input.split()

            if len(parts) < 2:
                print("Invalid command")
                continue

            command = parts[0].lower()
            item = parts[1].title()

            if command == "add":
                if item in prices:
                    cart.append(item)
                    print(item, "added")
                else:
                    print("Item not found")

            elif command == "remove":
                if item in cart:
                    cart.remove(item)
                    print(item, "removed")
                else:
                    print("Item not found")

            else:
                print("Invalid command")


shopping_cart()

Meaning

Dictionary:

prices = {"Apple": 2.7}

means Apple costs 2.7.

Empty cart:

cart = []

Add:

cart.append(item)

Remove:

cart.remove(item)

Check if item exists in shop:

if item in prices:

Check if item exists in cart:

if item in cart:

Sorted display:

for item in sorted(cart):

Total:

total = 0
total += price

total = 0 means start counting from zero.

total += price means:

total = total + price

Show vs Done

They are almost the same.

show = show cart and continue
done = show cart and stop

The only difference is:

break

done has break.
show does not.

18. Better Shopping Cart with Helper Function

This avoids repeating show code.

def shopping_cart():
    prices = {
        "Apple": 2.7,
        "Orange": 3.5,
        "Cola": 4.5,
        "Mascarpone": 14.9,
        "Beef": 22.4,
        "Pork": 18.9,
        "Nutella": 27.5
    }

    cart = []

    def show_cart():
        total = 0

        print("Shopping cart:")

        for item in sorted(cart):
            price = prices[item]
            total += price
            print(f"{item}: {price}")

        print(f"Total: {total:.2f}")

    while True:
        user_input = input("Enter command: ").strip()

        if user_input.lower() == "show":
            show_cart()

        elif user_input.lower() == "done":
            show_cart()
            break

        else:
            parts = user_input.split()

            if len(parts) < 2:
                print("Invalid command")
                continue

            command = parts[0].lower()
            item = parts[1].title()

            if command == "add":
                if item in prices:
                    cart.append(item)
                    print(item, "added")
                else:
                    print("Item not found")

            elif command == "remove":
                if item in cart:
                    cart.remove(item)
                    print(item, "removed")
                else:
                    print("Item not found")

            else:
                print("Invalid command")


shopping_cart()

19. Similar Shopping Cart Problems

To-Do List Manager

def todo_list():
    tasks = []

    while True:
        user_input = input("Enter command: ").strip()

        if user_input.lower() == "show":
            for task in sorted(tasks):
                print(task)

        elif user_input.lower() == "done":
            for task in sorted(tasks):
                print(task)
            break

        else:
            parts = user_input.split(maxsplit=1)

            if len(parts) < 2:
                print("Invalid command")
                continue

            command = parts[0].lower()
            task = parts[1].title()

            if command == "add":
                tasks.append(task)
                print(task, "added")

            elif command == "remove":
                if task in tasks:
                    tasks.remove(task)
                    print(task, "removed")
                else:
                    print("Item not found")

            else:
                print("Invalid command")


todo_list()

Food Order System

def food_order():
    menu = {
        "Burger": 12,
        "Pizza": 18,
        "Water": 2,
        "Coffee": 5
    }

    order = []

    while True:
        user_input = input("Enter command: ").strip()

        if user_input.lower() == "show":
            total = 0

            for item in sorted(order):
                print(item, menu[item])
                total += menu[item]

            print("Total:", total)

        elif user_input.lower() == "done":
            total = 0

            for item in sorted(order):
                print(item, menu[item])
                total += menu[item]

            print("Total:", total)
            break

        else:
            parts = user_input.split()

            if len(parts) < 2:
                print("Invalid command")
                continue

            command = parts[0].lower()
            item = parts[1].title()

            if command == "add":
                if item in menu:
                    order.append(item)
                else:
                    print("Item not found")

            elif command == "remove":
                if item in order:
                    order.remove(item)
                else:
                    print("Item not found")

            else:
                print("Invalid command")


food_order()

20. Bonus — Password Validator

Task

Create function:

is_valid_password()

Rules:

at least 8 characters
at least one digit
at least one uppercase letter
at least one lowercase letter
print which rule failed
return True or False
keep asking until password is accepted

Perfect Solution

def is_valid_password(password):
    valid = True

    if len(password) < 8:
        print("Password must be at least 8 characters long.")
        valid = False

    if not any(char.isdigit() for char in password):
        print("Password must contain at least one digit.")
        valid = False

    if not any(char.isupper() for char in password):
        print("Password must contain at least one uppercase letter.")
        valid = False

    if not any(char.islower() for char in password):
        print("Password must contain at least one lowercase letter.")
        valid = False

    return valid


while True:
    password = input("Create a password: ")

    if is_valid_password(password):
        print("Password accepted!")
        break
    else:
        print("Please try again.")

Important Methods

Length:

len(password)

Digit:

char.isdigit()

Uppercase:

char.isupper()

Lowercase:

char.islower()

At least one digit:

any(char.isdigit() for char in password)

No digit:

not any(char.isdigit() for char in password)

any(...) means at least one exists.
not any(...) means none exists.

21. Similar Validator Problems

PIN Validator

Rules:

exactly 4 digits
only numbers

def is_valid_pin(pin):
    if len(pin) != 4:
        print("PIN must be exactly 4 digits.")
        return False

    if not pin.isdigit():
        print("PIN must contain only digits.")
        return False

    return True


while True:
    pin = input("Create PIN: ")

    if is_valid_pin(pin):
        print("PIN accepted!")
        break
    else:
        print("Try again.")

Email Validator

Simple version:

def is_valid_email(email):
    valid = True

    if "@" not in email:
        print("Email must contain @.")
        valid = False

    if "." not in email:
        print("Email must contain a dot.")
        valid = False

    if len(email) < 5:
        print("Email is too short.")
        valid = False

    return valid


while True:
    email = input("Enter email: ")

    if is_valid_email(email):
        print("Email accepted!")
        break
    else:
        print("Try again.")

Username Validator

Rules:

at least 5 characters
starts with a letter
only letters and digits

def is_valid_username(username):
    valid = True

    if len(username) < 5:
        print("Username must be at least 5 characters.")
        valid = False

    if not username[0].isalpha():
        print("Username must start with a letter.")
        valid = False

    if not username.isalnum():
        print("Username must contain only letters and digits.")
        valid = False

    return valid


while True:
    username = input("Create username: ")

    if is_valid_username(username):
        print("Username accepted!")
        break
    else:
        print("Try again.")

22. File Handling Patterns

These may appear from lecture 7.

Write to file

"w" means write and overwrite old file.

name = input("What's your name? ")

with open("names.txt", "w") as file:
    file.write(name)

Append to file

"a" means append, add to end.

name = input("What's your name? ")

with open("names.txt", "a") as file:
    file.write(f"{name}\n")

\n means new line.

Read file

with open("names.txt") as file:
    lines = file.readlines()

for line in lines:
    print(line.rstrip())

rstrip() removes newline at the end.

Read file line by line

with open("names.txt") as file:
    for line in file:
        print(line.rstrip())

Read and sort names

with open("names.txt") as file:
    names = file.readlines()

for name in sorted(names):
    print(name.rstrip())

23. Common Mini Problems

Ask for 3 names and print sorted

def sorted_names():
    names = []

    for _ in range(3):
        name = input("Enter name: ")
        names.append(name)

    for name in sorted(names):
        print(name)


sorted_names()

Sum numbers

def sum_numbers():
    numbers = [int(x) for x in input("Enter numbers: ").split()]
    print(sum(numbers))


sum_numbers()

Average numbers

def average_numbers():
    numbers = [int(x) for x in input("Enter numbers: ").split()]
    average = sum(numbers) / len(numbers)
    print(average)


average_numbers()

Count positive numbers

def count_positive():
    numbers = [int(x) for x in input("Enter numbers: ").split()]

    count = 0

    for number in numbers:
        if number > 0:
            count += 1

    print(count)


count_positive()

Even numbers

def even_numbers():
    numbers = [int(x) for x in input("Enter numbers: ").split()]

    evens = []

    for number in numbers:
        if number % 2 == 0:
            evens.append(number)

    print(evens)


even_numbers()

number % 2 == 0 means number is even.

Dictionary lookup

def price_lookup():
    prices = {
        "Apple": 2.7,
        "Cola": 4.5
    }

    item = input("Enter item: ").title()

    if item in prices:
        print(prices[item])
    else:
        print("Item not found")


price_lookup()

24. Common Errors

IndentationError

Wrong:

def test():
print("hello")

Correct:

def test():
    print("hello")

Python needs indentation inside functions, loops, and if statements.

ValueError

Happens when conversion fails.

Example:

int("abc")

Fix:

try:
    x = int(input("Enter number: "))
except ValueError:
    print("Invalid number")

NameError

Happens when variable does not exist.

Wrong:

print(total)

before:

total = 0

Correct:

total = 0
print(total)

KeyError

Happens when dictionary key does not exist.

Wrong:

prices["Milk"]

if "Milk" is not in dictionary.

Correct:

if item in prices:
    print(prices[item])
else:
    print("Item not found")

IndexError

Happens when list position does not exist.

Wrong:

parts = ["add"]
item = parts[1]

Correct:

if len(parts) < 2:
    print("Invalid command")
else:
    item = parts[1]

TypeError

Example:

sum(["20", "30"])

Wrong because they are strings.

Correct:

numbers = [int(x) for x in ["20", "30"]]
sum(numbers)

25. Final Must-Memorize Patterns

Function

def function_name():
    ...

Call function

function_name()

or:

print(function_name())

Integer input

x = int(input("Enter number: "))

Float input

x = float(input("Enter number: "))

Validate number

while True:
    try:
        x = int(input("Enter number: "))
        break
    except ValueError:
        print("Invalid number")

Validate positive number

while True:
    try:
        x = float(input("Enter number: "))

        if x <= 0:
            print("Must be positive.")
        else:
            break

    except ValueError:
        print("Invalid number")

Many numbers in one input

numbers = [int(x) for x in input("Enter numbers: ").split()]

Sum

total = sum(numbers)

Average

average = sum(numbers) / len(numbers)

Empty list

items = []

Add to list

items.append(item)

Remove from list

items.remove(item)

Check item in list

if item in items:

Dictionary

prices = {"Apple": 2.7}

Dictionary lookup

prices[item]

Check item in dictionary

if item in prices:

Random number

import random

number = random.randint(1, 100)

Random choice from list

import random

word = random.choice(words)

Password checks

len(password) < 8


not any(char.isdigit() for char in password)


not any(char.isupper() for char in password)


not any(char.islower() for char in password)

Stop loop

break

Skip current loop

continue

Exit function

return

26. The 5 Most Useful Skeletons

Skeleton 1: Category Function

def category_function():
    name = input("Enter name: ")
    value = float(input("Enter value: "))

    if value < something:
        category = "Category 1"
    elif value < something:
        category = "Category 2"
    else:
        category = "Category 3"

    return {"name": name, "category": category}


print(category_function())

Use for BMI, age, temperature, discount.

Skeleton 2: Scores Function

def scores_function():
    name = input("Enter name: ")
    scores = [int(score) for score in input("Enter scores: ").split()]

    total = sum(scores)

    if total >= 91:
        grade = "A"
    elif total >= 81:
        grade = "B"
    else:
        grade = "F"

    return {"name": name, "grade": grade}


print(scores_function())

Use for grades, average, pass/fail.

Skeleton 3: Guessing Game

import random

def game():
    secret = random.randint(1, 100)
    attempts = 7

    while attempts > 0:
        try:
            guess = int(input("Enter guess: "))

            attempts -= 1

            if guess == secret:
                print("Correct!")
                return
            elif guess > secret:
                print("Too high!")
            else:
                print("Too low!")

            print("Attempts left:", attempts)

        except ValueError:
            print("Enter integer.")

    print("You lost. Number was", secret)


game()

Use for number guessing, dice, PIN, math quiz.

Skeleton 4: List Manager

def manager():
    items = []

    while True:
        user_input = input("Enter command: ").strip()

        if user_input.lower() == "show":
            for item in sorted(items):
                print(item)

        elif user_input.lower() == "done":
            for item in sorted(items):
                print(item)
            break

        else:
            parts = user_input.split()

            if len(parts) < 2:
                print("Invalid command")
                continue

            command = parts[0].lower()
            item = parts[1].title()

            if command == "add":
                items.append(item)

            elif command == "remove":
                if item in items:
                    items.remove(item)
                else:
                    print("Item not found")

            else:
                print("Invalid command")


manager()

Use for shopping cart, to-do list, contact list.

Skeleton 5: Validator

def is_valid(value):
    valid = True

    if condition_failed:
        print("Rule failed")
        valid = False

    if condition_failed:
        print("Rule failed")
        valid = False

    return valid


while True:
    value = input("Enter value: ")

    if is_valid(value):
        print("Accepted!")
        break
    else:
        print("Try again.")

Use for password, PIN, email, username.

Final Exam Memory

For this make-up, the most likely things are:

function
input
int / float
try / except
while True
for loop
list
dictionary
if / elif / else
sum
len
sorted
random.randint
append
remove
split
lower
title
strip
any
isdigit / isupper / islower
return dictionary

When you see a problem, first ask:

Is this a category problem?
Is this a list of numbers problem?
Is this a guessing game?
Is this a list manager?
Is this a validator?

Then use the matching skeleton.

Posted May 13, 2026, 7:26 AM UTC