code: def update(self, x):
      self._ewma.update(x)
      self._is_init = True
      self._ibc = self._lambd_sq + self._c_lambd_sq * self._ibc
  
imports: from __future__ import annotations
  import copy
  import math
  from river import base, stats
label_desc: Use image node_id 2 for calling the SampleInfo obj's underlying member method code with example usage: obj.update(x) without return types