code: def test_hifreqs(self):
      # For those freq, downsample2 should return zero
      for freq in [36, 40, 56, 64]:
          x = pure_tone(freq, sr=128)
          y = resample._downsample2(x)
          y_gt = 0 * y
          self.assertSimilar(y, y_gt, x, f"freq={freq}")
  
imports: import os
  import tempfile
  import uuid
  from pathlib import Path
  import math
  import random
  import unittest
  import resampy
  import torch
  from julius import resample, ResampleFrac
label_desc: Use image node_id 2 for calling the TestDownsample2 obj's underlying member method code with example usage: obj.test_hifreqs() without return types