old_contents: 
  class Coffee(object):
      def __init__(self, name: str, price: float):
          self.name = name
          self.price = price
  
  COFFEES = [Coffee('Americano', 1.50),
             Coffee('Cappuccino', 2.00),
             Coffee('Espresso', 1.30),
             Coffee('Latte Macchiato', 2.20),
             Coffee('Moccaccino', 2.30),]
  
  
  class CoffeeMachine(object):
      def __init__(self, name: str, factor: float = 1.0):
          self.name = name
          self.factor = factor
  
  MACHINES = [CoffeeMachine('Filter Machine'),
              CoffeeMachine('Pad Machine', 1.1),
              CoffeeMachine('Capsule Machine', 1.2),
              CoffeeMachine('Espresso Machine', 1.3),]
  
  
  def calculate_total_price(amount: int, price: float, factor: float):
      return round(amount * price * factor, 1)
  
  
  def make_coffee(amount: int, coffee: Coffee, machine: CoffeeMachine):
      if amount < 1:
          return 'Your ordered {} coffees. How many coffees again, please?'.format(amount)
      else:
          total = calculate_total_price(amount, coffee.price, machine.factor)
          if amount == 1:
              return 'Made one {} with a {} for only {:.2f}€.'.format(coffee.name, machine.name, total)
          else:
              return 'Made {} {}s with a {} for only {:.2f}€.'.format(amount, coffee.name, machine.name, total)
  
new_contents: 
  class Coffee(object):
      def __init__(self, name: str, price: float):
          self.name = name
          self.price = price
  
  COFFEES = [Coffee('Americano', 1.50),
             Coffee('Cappuccino', 2.00),
             Coffee('Espresso', 1.30),
             Coffee('Latte Macchiato', 2.20),
             Coffee('Moccaccino', 2.30),
  	   Coffee('Knallerboot', 5.00) ]
  	
  
  class CoffeeMachine(object):
      def __init__(self, name: str, factor: float = 1.0):
          self.name = name
          self.factor = factor
  
  MACHINES = [CoffeeMachine('Filter Machine'),
              CoffeeMachine('Pad Machine', 1.1),
              CoffeeMachine('Capsule Machine', 1.2),
              CoffeeMachine('Espresso Machine', 1.3),]
  
  
  def calculate_total_price(amount: int, price: float, factor: float):
      return round(amount * price * factor, 1)
  
  
  def make_coffee(amount: int, coffee: Coffee, machine: CoffeeMachine):
      if amount < 1:
          return 'Your ordered {} coffees. How many coffees again, please?'.format(amount)
      else:
          total = calculate_total_price(amount, coffee.price, machine.factor)
          if amount == 1:
              return 'Made one {} with a {} for only {:.2f}€.'.format(coffee.name, machine.name, total)
          else:
              return 'Made {} {}s with a {} for only {:.2f}€.'.format(amount, coffee.name, machine.name, total)
  
subject: Add Knallerboot Coffe