class_docstr: Normal noise generator. 
class_docstr_tok: ["Normal","noise","generator","."]
docstr: Constructor.
  
  Parameters
  ----------
  mu
      Mean of the normal noise.
  sigma
      Standard deviation of the noise.
code: def __init__(self, mu: float, sigma: float) -> None:
      """
      Constructor.
  
      Parameters
      ----------
      mu
          Mean of the normal noise.
      sigma
          Standard deviation of the noise.
      """
      self.mu = mu
      self.sigma = sigma
  
imports: import logging
  import os
  from abc import ABC, abstractmethod
  from copy import deepcopy
  from typing import TYPE_CHECKING, Any, Callable, Dict, Optional, Tuple, Union, cast
  import numpy
  from tqdm import tqdm
  from alibi.api.defaults import DEFAULT_DATA_CFRL, DEFAULT_META_CFRL
  from alibi.api.interfaces import Explainer, Explanation, FitMixin
  from alibi.explainers.backends.cfrl_base import generate_empty_condition, get_classification_reward, get_hard_distribution, identity_function
  from alibi.utils.frameworks import Framework, has_pytorch, has_tensorflow
label_desc: Use image node_id 1 to create a new NormalActionNoise object  with example: obj = NormalActionNoise(mu, sigma)