diff --git a/synphot/tests/test_models.py b/synphot/tests/test_models.py
index 36cd47c..e5c631a 100644
--- a/synphot/tests/test_models.py
+++ b/synphot/tests/test_models.py
@@ -26,8 +26,8 @@
 
 # LOCAL
 from synphot import specio, units
-from synphot.models import (BlackBody1D, ConstFlux1D, Empirical1D, PowerLawFlux1D,
-                      get_metadata)
+from synphot.models import (BlackBody1D, ConstFlux1D, Empirical1D,
+                            PowerLawFlux1D, get_metadata)
 
 
 def setup_module(module):
diff --git a/synphot/tests/test_observation.py b/synphot/tests/test_observation.py
index df13df3..032ea7d 100644
--- a/synphot/tests/test_observation.py
+++ b/synphot/tests/test_observation.py
@@ -21,16 +21,21 @@
 from synphot.tests.test_units import _area
 from synphot import exceptions, units
 from synphot.compat import HAS_SPECUTILS  # noqa
-from synphot.models import (BlackBodyNorm1D, Box1D, ConstFlux1D, Empirical1D,
-                      GaussianFlux1D)
+from synphot.models import (
+    BlackBodyNorm1D, Box1D, ConstFlux1D, Empirical1D, GaussianFlux1D
+)
 from synphot.observation import Observation
 from synphot.spectrum import SourceSpectrum, SpectralElement
 
 # Global test data files
 _specfile = get_pkg_data_filename(
-    os.path.join('data', 'grw_70d5824_stisnic_005.fits'), package='synphot.tests')
+    os.path.join('data', 'grw_70d5824_stisnic_005.fits'),
+    package='synphot.tests'
+)
 _bandfile = get_pkg_data_filename(
-    os.path.join('data', 'hst_acs_hrc_f555w.fits'), package='synphot.tests')
+    os.path.join('data', 'hst_acs_hrc_f555w.fits'),
+    package='synphot.tests'
+)
 
 
 class TestObservation:
diff --git a/synphot/tests/test_spectrum_source.py b/synphot/tests/test_spectrum_source.py
index 5e286e6..b35cf46 100644
--- a/synphot/tests/test_spectrum_source.py
+++ b/synphot/tests/test_spectrum_source.py
@@ -21,7 +21,9 @@
 from astropy.utils.exceptions import AstropyUserWarning
 
 # LOCAL
-from synphot.tests.test_units import _area, _wave, _flux_jy, _flux_photlam, _flux_vegamag
+from synphot.tests.test_units import (
+    _area, _wave, _flux_jy, _flux_photlam, _flux_vegamag
+)
 from synphot import exceptions, units
 from synphot.compat import ASTROPY_LT_4_0
 from synphot.compat import HAS_SPECUTILS  # noqa