old_contents: # -*- coding: utf-8 -*-
  #
  # Copyright (C) 2012 Alexander Shorin
  # All rights reserved.
  #
  # This software is licensed as described in the file COPYING, which
  # you should have received as part of this distribution.
  #
  
  
  class DummyMixIn(object):
      _input_buffer = ''
  
      def flush(self):
          pass
  
  
  class CallLogger(object):
  
      def __init__(self, func):
          self.func = func
          self.was_called = False
  
      def __call__(self, *args, **kwargs):
          self.was_called = True
          return self.func(*args, **kwargs)
  
  
  def track_call(func):
      return CallLogger(func)
  
new_contents: # -*- coding: utf-8 -*-
  #
  # Copyright (C) 2012 Alexander Shorin
  # All rights reserved.
  #
  # This software is licensed as described in the file COPYING, which
  # you should have received as part of this distribution.
  #
  
  
  class DummyMixIn(object):
      _input_buffer = ''
  
      def flush(self):
          pass
  
      def close(self):
          pass
  
  
  class CallLogger(object):
  
      def __init__(self, func):
          self.func = func
          self.was_called = False
  
      def __call__(self, *args, **kwargs):
          self.was_called = True
          return self.func(*args, **kwargs)
  
  
  def track_call(func):
      return CallLogger(func)
  
subject: Fix DummyMixIn.