class_docstr: Class that maintains an exponential moving average.
code: def update(self, value):
      self._numerator = (
          self._momentum * self._denominator
          + (1 - self._momentum) * value
      )
      self._denominator = self._momentum * self._denominator + (
          1 - self._momentum
      )
  
file_path: singa/examples/model_selection/TRAILS-Database-Native-Model-Selection/internal/ml/model_selection/src/controller/sampler_rl/reinforcement_learning.py
imports: from src.controller.core.sample import Sampler
  from src.search_space.core.space import SpaceWrapper
  from src.search_space.core.model_params import ModelMicroCfg
  from src.third_pkg.models import CellStructure
label_desc: Use image node_id 2 for calling the ExponentialMovingAverage obj's underlying member method code with example usage: obj.update(value) without return types