code: def testEmpty(self):
      # Empty input returns no onsets
      self.assertComputeFails(OnsetRate(), [])
  
file_path: essentia/test/src/unittests/rhythm/test_onsetrate.py
imports: from essentia_test import *
  from numpy import random
label_desc: Use image node_id 2 for calling the TestOnsetRate obj's underlying member method code with example usage: obj.testEmpty() without return types