code: def testConstant(self):
      SC = SpectralContrast(sampleRate=44100)
      sc, valleys = SC([0.5] * 1025)
      self.assertAlmostEqual(numpy.mean(sc), -1)
      self.assertAlmostEqual(numpy.mean(valleys), -0.6931471825, 1e-7)
  
file_path: essentia/test/src/unittests/spectral/test_spectralcontrast.py
imports: from essentia_test import *
label_desc: Use image node_id 4 for calling the TestSpectralContrast obj's underlying member method code with example usage: obj.testConstant() without return types