code: def test_get_session_silence_mean_pass(self, sampler, mean, var):
      sampler.mean_silence = mean
      sampler.mean_silence_var = var
      sampled_silence_mean = sampler.get_session_silence_mean()
      assert 0 <= sampled_silence_mean <= 1
  
imports: import os
  import numpy
  import pytest
  import torch
  from omegaconf import DictConfig
  from nemo.collections.asr.parts.utils.data_simulation_utils import DataAnnotator, SpeechSampler, add_silence_to_alignments, binary_search_alignments, get_cleaned_base_path, get_split_points_in_alignments, normalize_audio, read_noise_manifest
  from nemo.collections.asr.parts.utils.manifest_utils import get_ctm_line
label_desc: Use image node_id 4 for calling the TestSpeechSampler obj's underlying member method code with example usage: obj.test_get_session_silence_mean_pass(sampler, mean, var) without return types