class_docstr: DenStream Micro-cluster class
code: def fading_function(self, time):
      return 2 ** (-self.decaying_factor * time)
  
imports: from __future__ import annotations
  import copy
  import math
  from abc import ABCMeta
  from collections import defaultdict, deque
  from river import base, utils
label_desc: Use image node_id 9 for calling the DenStreamMicroCluster obj's underlying member method code with example usage: obj.fading_function(time) and returns: unknown