old_contents: from timeit import default_timer as python_timer
  
  
  class Timer(object):
      __slots__ = ('start', 'format')
  
      def __init__(self, format=None, **kwargs):
          self.start = python_timer()
          self.format = format
  
      def taken(self):
          return (self.format.format if self.format else float)(python_timer() - self.start)
  
  timer = Timer
  
new_contents: from timeit import default_timer as python_timer
  
  
  class Timer(object):
      __slots__ = ('start', 'round_to')
  
      def __init__(self, round_to=None, **kwargs):
          self.start = python_timer()
          self.round_to = round_to
  
      @property
      def elapsed(self):
          return round(self.start, self.round_to) if self.round_to else self.start
  
      def __float__(self):
          return self.elapsed
  
      def __int__(self):
          return int(round(self.elapsed))
  
  timer = Timer
  
subject: Implement desired timer behaviour