Codestyle fixes.

Author: hpparvi

specreduce/tests/test_tilt_correction.py

@@ -1,12 +1,13 @@
 import numpy as np
 import pytest
 from astropy.modeling import models
-from astropy.nddata import NDData, StdDevUncertainty
+from astropy.nddata import StdDevUncertainty
 from astropy.wcs import WCS
 
 from specreduce.tilt_correction import TiltCorrection, diff_poly2d_x
 from specreduce.utils.synth_data import make_2d_arc_image
 
+
 # Arc frame creation code taken from Tim Pickering's example notebook
 @pytest.fixture
 def mk_arc_frames():