text: #!/usr/bin/env python3
  # -*- coding: utf-8 -*-
  
  from contextlib import contextmanager
  
  
  @contextmanager
  def log(name):
      print("[%s] start..." % name)
      yield
      print("[%s] end." % name)
  
  
  with log("DEBUG"):
      print("Hello, world!")
      print("Hello, Python!")
  