old_contents: """
  Taken from: https://gist.github.com/acdha/4068406
  """
  
  import sys
  from timeit import default_timer
  
  
  class Timer(object):
      """Context Manager to simplify timing Python code
      Usage:
          with Timer('key step'):
              ... do something ...
      """
      def __init__(self, context=None):
          self.timer = default_timer
  
          if context is None:
              import inspect
              caller_frame = inspect.stack()[1]
              frame = caller_frame[0]
              info = inspect.getframeinfo(frame)
  
              context = '%s (%s:%s)' % (info.function, info.filename, info.lineno)
  
          self.context = context
  
      @property
      def elapsed(self):
          end = self.timer()
          return (end - self.start) * 1000
  
      def restart(self):
          self.start = self.timer()
  
      def __enter__(self):
          self.start = self.timer()
          return self
  
      def __exit__(self, *args):
          print >>sys.stderr, '%s: %f ms' % (self.context, self.elapsed)
  
new_contents: """
  Taken from: https://gist.github.com/acdha/4068406
  """
  
  import sys
  import inspect
  from timeit import default_timer
  
  
  class Timer(object):
      """Context Manager to simplify timing Python code
      Usage:
          with Timer('key step'):
              ... do something ...
      """
      def __init__(self, context=None, summary=True):
          self.timer = default_timer
          self.summary = summary
  
          if context is None:
              caller_frame = inspect.stack()[1]
              frame = caller_frame[0]
              info = inspect.getframeinfo(frame)
  
              context = '%s (%s:%s)' % (info.function, info.filename, info.lineno)
  
          self.context = context
  
      @property
      def elapsed(self):
          end = self.timer()
          return (end - self.start) * 1000
  
      def restart(self):
          self.start = self.timer()
  
      def __enter__(self):
          self.start = self.timer()
          return self
  
      def __exit__(self, *args):
          if self.summary:
              print >>sys.stderr, '%s: %f ms' % (self.context, self.elapsed)
  
subject: Add summary option