a pizza_maker.py

class PizzaMaker:
  
  def create_pizza(self, **pizza_properties):
  
    pizza_type = pizza_properties["ptype"]
    pizza_class = get_pizza_class(pizza_type)
    if pizza_class is None:
      raise UnknownPizaType(pizza_type)
      
    del pizza_properties["ptype"]
    pizza = pizza_class(**pizza_properties)
    
    return pizza

b margherita.py

class PizzaMargherita(DBModel):
  id = column.Int....
  created_at = column.DateTime....
  created_by = column.fk...
  
  cheeze_type = column.Enum...
  with_bazil = column.Bool...
  ....