diff --git a/netcdf_examples/quantize_test/test_quantize.py b/netcdf_examples/quantize_test/test_quantize.py
index 63b3c57..b84715a 100644
--- a/netcdf_examples/quantize_test/test_quantize.py
+++ b/netcdf_examples/quantize_test/test_quantize.py
@@ -61,9 +61,9 @@ def test_check_output(self):
                             '{}.cdl'.format(netcdf_fileroot)],
                            cwd=self.test_dir)
             test_results = netCDF4.Dataset(
-                os.path.join(self.test_dir, netcdf_file)['field'][:])
+                os.path.join(self.test_dir, netcdf_file))['field'][:]
             expected = netCDF4.Dataset(
-                os.path.join(self.test_dir, reference_ncfile)['field'][:])
+                os.path.join(self.test_dir, reference_ncfile))['field'][:]
             diff = test_results - expected
             result = numpy.allclose(test_results, expected, rtol=self.tolerance)
             if not result: