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9. Functions 🪄

Learn how to create reusable magic spells (functions) in Python!


Level Up with Function Magic! 🪄

Hey coding champions! Remember how we used loops to repeat actions in our last adventure? Now it's time to learn something SUPER powerful - Functions! Think of functions as your very own magic spells that you can create and use whenever you want! Just like how a wizard stores their favorite spells in a spellbook, functions let you save your code magic for later! 🧙‍♂️

Today's Quest! 🎯

You'll learn how to:

  • Create your own magic spells (functions)! 🪄
  • Make spells that can receive magic ingredients (arguments)! 🧪
  • Return magical results from your spells! ✨
  • Organize your spellbook (code) like a master wizard! 📚

Creating Your First Spell (Function)! 🎯

Remember how we used loops to fight multiple enemies? Let's create a function for that!

def battle_cry():
    print("Ready for adventure! ⚔️")
    print("Enemies beware! 🛡️")
    print("Victory shall be mine! 🏆")
 
# Use your spell (call the function)
battle_cry()

Spells with Magic Ingredients (Arguments)! 🧪

def greet_player(player_name, player_class):
    print(f"Welcome, {player_name} the {player_class}! 🌟")
    
# Use the spell with different ingredients
greet_player("Alex", "Warrior")
greet_player("Luna", "Mage")
 
# Remember our healing loop? Let's make it a function!
def heal_player(current_health, potion_power):
    while current_health < 100:
        current_health += potion_power
        print(f"Healing... Current health: {current_health} ❤️")
    return current_health  # Send back the new health value!

Spells that Return Magic (Return Values)! ✨

def calculate_damage(weapon_power, player_level):
    total_damage = weapon_power * (1 + player_level/10)
    return total_damage
 
# Use the spell in battle!
sword_damage = calculate_damage(25, 5)
print(f"Your attack deals {sword_damage} damage! ⚔️")

Combining Multiple Spells! 🔮

def check_inventory(items):
    print("Checking inventory... 🎒")
    for item in items:  # Using our loop knowledge!
        if item == "Magic Key":  # Using our conditional knowledge!
            return True
    return False
 
def open_treasure_chest(has_key):
    if has_key:
        print("Opening the treasure chest... 🗝️")
        print("You found magical loot! ✨")
    else:
        print("You need a Magic Key to open this chest! 🔒")
 
# Let's use both spells together!
player_inventory = ["Sword", "Shield", "Magic Key", "Potion"]
has_magic_key = check_inventory(player_inventory)
open_treasure_chest(has_magic_key)

🎮 Mini-Game: The Magical Restaurant!

Let's create a pizza-making game using functions!

def prepare_dough(pizza_size):
    print(f"Preparing {pizza_size} pizza dough... 🥟")
    return "Ready dough"
 
def add_toppings(toppings):
    print("Adding magical toppings... ✨")
    for topping in toppings:  # Look, we're using loops!
        print(f"Adding {topping} 🧪")
 
def bake_pizza(dough, temperature):
    if temperature > 9000:  # Dragon-fire temperature!
        print("Baking with dragon fire! 🐲")
    else:
        print("Baking with regular fire! 🔥")
    return "Delicious Pizza"
 
# Let's make a pizza!
toppings = ["Mushrooms", "Dragon Peppers", "Magic Cheese"]
dough = prepare_dough("large")
add_toppings(toppings)
final_pizza = bake_pizza(dough, 9001)
print(f"Enjoy your {final_pizza}! 🍕")

🌟 Super Challenge: Create a Battle System!

def choose_character(name, character_class):
    # Your code here: Set up initial stats based on class
    pass
 
def attack(attacker_power, defender_health):
    # Your code here: Calculate damage and remaining health
    pass
 
def use_special_ability(character_class):
    # Your code here: Different special move for each class
    pass
 
# Example battle sequence
player = choose_character("Hero", "Warrior")
enemy_health = 100
 
while enemy_health > 0:  # Look, we're using while loops!
    # Your battle code here!
    pass

🎯 Debug Mission: Fix the Spell Book!

Can you spot what's wrong with these magical functions?

# Bug 1: Why doesn't this spell work?
def add_to_inventory(item)
    inventory.append(item)
    print(f"Added {item} to inventory!")
 
# Bug 2: What's wrong with this healing spell?
def heal():
    health = 100
    return health
player_health = 50
heal()
print(player_health)  # Still 50! Why?
 
# Bug 3: Can you spot the scope error?
def check_mana():
    mana = 100
print(mana)  # Why can't we see the mana here?

Final Boss Challenge: Create a Complete Adventure Game!

def start_adventure(player_name):
    """
    Create functions for:
    1. Player creation
    2. Battle system
    3. Inventory management
    4. Quest tracking
    5. Level up system
    
    Use all we've learned:
    - Strings for messages
    - Conditionals for decisions
    - Loops for repeated actions
    - Functions to organize it all!
    """
    pass
 
# Your code here!

Practice Quest: The Function Benefits Collector!

Let's create a magical library of function benefits:

def list_benefits():
    return [
        "More organized spellbook",
        "More readable magic",
        "Easier spell reuse",
        "Sharing spells with other wizards"
    ]
 
def build_sentence(benefit):
    return f"{benefit} is a benefit of functions! ✨"
 
def share_magical_knowledge():
    benefits = list_benefits()
    for benefit in benefits:  # Using our loop powers!
        print(build_sentence(benefit))
 
# Let's share our knowledge!
share_magical_knowledge()

Remember:

  • Functions are like spells in your spellbook
  • They can take magical ingredients (arguments)
  • They can return magical results
  • You can use them over and over
  • They make your code more organized and powerful!

Ready to create your own magical functions? Let's code! 🚀

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