old_contents: from .entity import Entity, Player, NPC
  
  def default_ordering(entity):
      return entity.speed
  
  
  class Scene(object):
      def __init__(self, canvas, entities, order_key=default_ordering):
          if not order_key:
              self.order_key = default_ordering
  
          self.entities = entities
          self.order_key = order_key
          self.canvas = canvas
  
  
      def start(self):
          for entity in sorted(self.entities, key=self.order_key):
              action = entity.next_action()
              if action.requires_target():
                  targets = entity.select_target(self.entities)
                  action.execute(targets)
              else:
                  action.execute()
  
new_contents: from .entity import Entity, Player, NPC
  
  def default_ordering(entity):
      return entity.speed
  
  
  class Scene(object):
      def __init__(self, entities, order_key=default_ordering):
          if not order_key:
              self.order_key = default_ordering
  
          self.entities = entities
          self.order_key = order_key
  
  
      def start(self):
          for entity in sorted(self.entities, key=self.order_key):
              action = entity.next_action()
              if action.requires_target():
                  targets = entity.select_target(self.entities)
                  action.execute(targets)
              else:
                  action.execute()
  
subject: remove canvas parameter