old_contents: import time
  
  class Cache:
      def __init__(self, func, expire_seconds=None):
          self.func = func
          self.expire_seconds = expire_seconds
          self.last_result = None
          self.last_time = None
          self.last_args = None
          self.last_kwargs = None
          
      def __call__(self, *args, **kwargs):
          call_time = time.time()
          if args != self.last_args or kwargs != self.last_kwargs or \
             self.last_time is None or call_time > self.last_time + self.expire_seconds:
              print "cache miss"
              self.last_result = self.func(*args, **kwargs)
              self.last_time = call_time
              self.last_args = args
              self.last_kwargs = kwargs
              
          return self.last_result
new_contents: import time
  
  class Cache:
      def __init__(self, func, expire_seconds=None):
          self.func = func
          self.expire_seconds = expire_seconds
          self.last_result = None
          self.last_time = None
          self.last_args = None
          self.last_kwargs = None
          
      def __call__(self, *args, **kwargs):
          call_time = time.time()
          if args != self.last_args or kwargs != self.last_kwargs or \
             self.last_time is None or call_time > self.last_time + self.expire_seconds:
              self.last_result = self.func(*args, **kwargs)
              self.last_time = call_time
              self.last_args = args
              self.last_kwargs = kwargs
              
          return self.last_result
subject: Remove cache miss print.