code: def test_spectral_spread(self):
      np.testing.assert_almost_equal(
          spectral_spread(const0, Fs), 0.0, decimal=5
      )
      np.testing.assert_almost_equal(
          spectral_spread(const1, Fs), 2.811883163207112e-06, decimal=5
      )
      np.testing.assert_almost_equal(
          spectral_spread(constNeg, Fs),
          2.811883163207112e-06,
          decimal=5,
      )
      np.testing.assert_almost_equal(
          spectral_spread(constF, Fs), 2.657703172211011e-06, decimal=5
      )
      np.testing.assert_almost_equal(
          spectral_spread(lin, Fs), 138.77058121011598, decimal=5
      )
      np.testing.assert_almost_equal(
          spectral_spread(lin0, Fs), 142.68541769470383, decimal=5
      )
      np.testing.assert_almost_equal(
          spectral_spread(wave, Fs), 3.585399057660381e-05, decimal=5
      )
      np.testing.assert_almost_equal(
          spectral_spread(offsetWave, Fs), 2.0000000000692015, decimal=5
      )
      np.testing.assert_almost_equal(
          spectral_spread(noiseWave, Fs), 165.48999545678365, decimal=5
      )
  
imports: import unittest
  import numpy
  from tsfel.feature_extraction.features import *
label_desc: Use image node_id 41 for calling the TestFeatures obj's underlying member method code with example usage: obj.test_spectral_spread() without return types