code: def testEmpty(self):
      mags = []
      phases = []
  
      self.assertEqualVector(PolarToCartesian()(mags, phases), [])
  
imports: from essentia_test import *
  from math import sin, cos
label_desc: Use image node_id 1 for calling the TestPolarToCartesian obj's underlying member method code with example usage: obj.testEmpty() without return types