code: def test_constant(self):
      x = th.ones(2048)
      for zeros in [4, 10]:
          for freq in [0.01, 0.1]:
              y_high = filters.highpass_filter(x, freq, zeros=zeros)
              self.assertLessEqual(
                  y_high.abs().mean(), 1e-6, (zeros, freq)
              )
  
imports: import random
  import unittest
  import torch
  from julius.core import pure_tone
  from julius import filters
label_desc: Use image node_id 5 for calling the TestHighPassFilters obj's underlying member method code with example usage: obj.test_constant() without return types