code: def testNegatives(self):
      result = Variance()([3, 7, -45, 2, -1, 0])
      self.assertAlmostEqual(result, 315.888889)
  
file_path: essentia/test/src/unittests/stats/test_variance.py
imports: from essentia_test import *
label_desc: Use image node_id 5 for calling the TestVariance obj's underlying member method code with example usage: obj.testNegatives() without return types