code: def testEmpty(self):
      input1 = []
      input2 = []
      self.assertEqualVector(self.add(input1, input2), [])
      self.assertEqualVector(self.sub(input1, input2), [])
      self.assertEqualVector(self.prod(input1, input2), [])
      self.assertEqualVector(self.div(input1, input2), [])
  
file_path: essentia/test/src/unittests/standard/test_binaryoperator.py
imports: from essentia_test import *
label_desc: Use image node_id 4 for calling the TestBinaryOperator obj's underlying member method code with example usage: obj.testEmpty() without return types