def test_iteritems(self): x = TimeSeries([1, 2, 3, 4],[1, 4, 9, 16]) i = x.iteritems() nextt = next(i) self.assertTrue ( nextt == (1, 1) ) nextt = next(i) self.assertTrue ( nextt == (2, 4) ) self.assertTrue (len(nextt) ==2 )