code: def testNegatives(self):
      result = Mean()([3, 7, -45, 2, -1, 0])
      self.assertAlmostEqual(result, -5.666666666)
  
file_path: essentia/test/src/unittests/stats/test_mean.py
imports: from essentia_test import *
label_desc: Use image node_id 5 for calling the TestMean obj's underlying member method code with example usage: obj.testNegatives() without return types