code: def test_triangle_freqs_wrong_norm(self):
      f = filterbank(10, 1024)
      with self.assertRaises(ValueError):
          f.set_norm(-1)
  
imports: import numpy
  from numpy.testing import TestCase, assert_equal, assert_almost_equal
  from _tools import assert_warns
  from aubio import fvec, cvec, filterbank, float_type
label_desc: Use image node_id 14 for calling the aubio_filterbank_mel_test_case obj's underlying member method code with example usage: obj.test_triangle_freqs_wrong_norm() without return types