diff --git a/materials/make_pizzas_ruff_demo.py b/materials/make_pizzas_ruff_demo.py
index af06ecb..dd21416 100644
--- a/materials/make_pizzas_ruff_demo.py
+++ b/materials/make_pizzas_ruff_demo.py
@@ -1,17 +1,17 @@
-from italianfood.ovens import bake_pizza
-from italianfood.dough import PizzaDough
+
 import numpy as np
-import time
-pizzaName='Hello pizza'
+
+from italianfood.dough import PizzaDough
+from italianfood.ovens import bake_pizza
+
+pizzaName = "Hello pizza"
+
+
 class Pizza:
     dough: PizzaDough
-    num_pizzas:int=1
+    num_pizzas: int = 1
     is_ready: bool = False
-    some_array:np.ndarray|None =None
-
-
-
-
+    some_array: np.ndarray | None = None
 
     def __init__(self, dough, num_pizza_balls):
         if num_pizza_balls < 1:
@@ -19,46 +19,48 @@ class Pizza:
         self.num_pizzas = num_pizza_balls
         self.dough = dough
         self.make_pizza_balls()
+
     def make_pizza_balls(self):
         self.weight_per_pizza_ball = self.dough.total_weight / self.num_pizzas
-        print(f"Each Pizza will be made out of {self.weight_per_pizza_ball} g dough.\n...")
+        print(
+            f"Each Pizza will be made out of {self.weight_per_pizza_ball} g dough.\n..."
+        )
         print("Now imagine expert pizza tossing skills!\n...")
 
-
-
         return self
+
     def add_toppings(self, toppings):
         self.toppings = toppings
         print(f"Adding {self.toppings} to pizza(s).\n...")
         return self
 
 
-
-
-
 def make_margherita_pizza(num_pizzas: int = 1):
-    total_flour_weight = 180   * num_pizzas
-    total_water_weight= 126*num_pizzas
-    total_salt_weight =2 *num_pizzas
-    total_yeast_weight=1* num_pizzas
+    total_flour_weight = 180 * num_pizzas
+    total_water_weight = 126 * num_pizzas
+    total_salt_weight = 2 * num_pizzas
+    total_yeast_weight = 1 * num_pizzas
 
-    dough=PizzaDough(flour_weight=total_flour_weight,water_weight=total_water_weight,salt_weight=total_salt_weight,yeast_weight=total_yeast_weight)
+    dough = PizzaDough(
+        flour_weight=total_flour_weight,
+        water_weight=total_water_weight,
+        salt_weight=total_salt_weight,
+        yeast_weight=total_yeast_weight,
+    )
 
-    toppings = ["tomato sauce", "mozzarella cheese", 'fresh basil']
+    toppings = ["tomato sauce", "mozzarella cheese", "fresh basil"]
 
-    pizza = Pizza(dough=dough,num_pizza_balls=num_pizzas)
+    pizza = Pizza(dough=dough, num_pizza_balls=num_pizzas)
     pizza.add_toppings(toppings)
 
-
-
     baked_pizza = bake_pizza(pizza)
 
     return baked_pizza
 
+
 import pandas
 
-df = pandas.DataFrame({
-    'col_a': [i for i in range(20)],
-    'col_b': [j for j in range(20, 40)]
-})
-df.drop(columns='col_b', inplace=True)
\ No newline at end of file
+df = pandas.DataFrame(
+    {"col_a": [i for i in range(20)], "col_b": [j for j in range(20, 40)]}
+)
+df.drop(columns="col_b", inplace=True)
diff --git a/materials/part2_packages_editable_install.pptx b/materials/part2_packages_editable_install.pptx
index aeaf1af..c68d5a0 100644
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diff --git a/materials/part3_repo_structure.pptx b/materials/part3_repo_structure.pptx
index c53b76c..6bf095b 100644
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diff --git a/materials/part5_environments.pptx b/materials/part5_environments.pptx
index 5dc31c9..d8ae4de 100644
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diff --git a/materials/part6_summary.pptx b/materials/part6_summary.pptx
index 323d2f3..32ad1a8 100644
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