code: def testEmptyUseOnset(self):
      input = []
      expected = [0, 0, 0, 0]
      result = self.runInstance(
          input, useBands=False, useOnset=True, poolInit=True
      )
      self.assertEqualVector(result, expected)
  
file_path: essentia/test/src/unittests/rhythm/test_rhythmextractor.py
imports: from essentia_test import *
  from essentia.streaming import RhythmExtractor
  from essentia.standard import MonoLoader, RhythmExtractor
  from math import fabs
label_desc: Use image node_id 8 for calling the TestRhythmExtractor obj's underlying member method code with example usage: obj.testEmptyUseOnset() without return types