code: def set_memcache_timeout_policy(self, func):
      
      if func is None:
        func = self.default_memcache_timeout_policy
      elif isinstance(func, (int, long)):
        func = lambda unused_key, flag=func: flag
      self._memcache_timeout_policy = func
docs: Set the policy function for memcache timeout (expiration).
  
      Args:
        func: A function that accepts a key instance as argument and returns
          an integer indicating the desired memcache timeout.  May be None.
  
      If the function returns 0 it implies the default timeout.