code: def testOne(self):
      result = Variance()([100])
      self.assertAlmostEqual(result, 0)
  
file_path: essentia/test/src/unittests/stats/test_variance.py
imports: from essentia_test import *
label_desc: Use image node_id 3 for calling the TestVariance obj's underlying member method code with example usage: obj.testOne() without return types