code: def test_operator_mel_filter_bank_vs_python():
      for device in ["cpu", "gpu"]:
          for batch_size in [1, 3]:
              for normalize in [True, False]:
                  for mel_formula in ["htk", "slaney"]:
                      for (
                          nfilter,
                          sample_rate,
                          freq_low,
                          freq_high,
                          shape,
                          layout,
                      ) in [
                          (4, 16000.0, 0.0, 8000.0, (17,), "f"),
                          (4, 16000.0, 0.0, 8000.0, (17, 1), "ft"),
                          (128, 16000.0, 0.0, 8000.0, (513, 100), "ft"),
                          (
                              128,
                              48000.0,
                              0.0,
                              24000.0,
                              (513, 100),
                              "ft",
                          ),
                          (
                              128,
                              16000.0,
                              0.0,
                              8000.0,
                              (10, 513, 100),
                              "Ctf",
                          ),
                          (
                              128,
                              48000.0,
                              4000.0,
                              24000.0,
                              (513, 100),
                              "tf",
                          ),
                          (
                              128,
                              44100.0,
                              0.0,
                              22050.0,
                              (513, 100),
                              "tf",
                          ),
                          (
                              128,
                              44100.0,
                              1000.0,
                              22050.0,
                              (513, 100),
                              "tf",
                          ),
                      ]:
                          yield (
                              check_operator_mel_filter_bank_vs_python,
                              device,
                              batch_size,
                              shape,
                              nfilter,
                              sample_rate,
                              freq_low,
                              freq_high,
                              normalize,
                              mel_formula,
                              layout,
                          )
  
imports: from nvidia.dali.pipeline import Pipeline
  import nvidia.dali.ops
  import numpy
  from functools import partial
  from test_utils import compare_pipelines
  from test_utils import RandomlyShapedDataIterator
  import librosa
label_desc: Use image node_id 3 for calling a global function with example usage: test_operator_mel_filter_bank_vs_python() without return types