code: def test_calculate_sdr_numpy(self):
      atol = 1e-6
      random_seed = 42
      num_examples = 50
      num_samples = 2000
  
      _rng = np.random.default_rng(seed=random_seed)
  
      for n in range(num_examples):
          # Generate signal
          target = _rng.normal(size=num_samples)
          # Adjust the estimate
          golden_sdr = _rng.integers(low=-10, high=10)
          estimate = target * (1 + 10 ** (-golden_sdr / 20))
  
          # UUT
          estimated_sdr = calculate_sdr_numpy(
              estimate=estimate, target=target, remove_mean=False
          )
  
          assert np.isclose(
              estimated_sdr, golden_sdr, atol=atol
          ), f"Example {n}: estimated ({estimated_sdr}) not matching the actual value ({golden_sdr})"
  
          # Add random mean and use remove_mean=True
          # SDR should not change
          target += _rng.uniform(low=-10, high=10)
          estimate += _rng.uniform(low=-10, high=10)
  
          # UUT
          estimated_sdr = calculate_sdr_numpy(
              estimate=estimate, target=target, remove_mean=True
          )
  
          assert np.isclose(
              estimated_sdr, golden_sdr, atol=atol
          ), f"Example {n}: estimated ({estimated_sdr}) not matching the actual value ({golden_sdr})"
  
imports: import os
  from collections import namedtuple
  from typing import List, Type, Union
  import librosa
  import matplotlib.pyplot
  import numpy
  import pytest
  import scipy
  import soundfile
  import torch
  from nemo.collections.asr.parts.preprocessing.segment import AudioSegment
  from nemo.collections.asr.parts.utils.audio_utils import SOUND_VELOCITY
  from nemo.collections.asr.parts.utils.audio_utils import calculate_sdr_numpy, convmtx_mc_numpy, db2mag, estimated_coherence, generate_approximate_noise_field, get_segment_start, mag2db, pow2db, rms, select_channels, theoretical_coherence, toeplitz
label_desc: Use image node_id 4 for calling the TestAudioUtilsElements obj's underlying member method code with example usage: obj.test_calculate_sdr_numpy() without return types