code: def testConstantInput(self):
      # When input is constant should yiled zero
      bandsgain = [2.0, 3.0, 2.0, 1.0, 1.2, 2.0, 3.0, 2.5]
      spectrum = [1] * len(bandsgain)
      tempoScale = TempoScaleBands(bandsGain=bandsgain)
      i = 0
      while i < 10:
          scaledbands, cumul = tempoScale(spectrum)
          i += 1
  
      self.assertEqualVector(scaledbands, zeros(len(bandsgain)))
      self.assertEqual(cumul, 0.0)
  
file_path: essentia/test/src/unittests/rhythm/test_temposcalebands.py
imports: from essentia_test import *
label_desc: Use image node_id 2 for calling the TestTempoScaleBands obj's underlying member method code with example usage: obj.testConstantInput() without return types