old_contents: #http://pytest.org/latest/
  
  import messages
  
  def test_messenger():
      pass
  
  
new_contents: #http://pytest.org/latest/
  
  #HOW TO USE PY.TEST
  # On this level of complexity of test simple run: py.test
  
  
  import messages
  
  def test_messenger():
      pass
  
  
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