diff --git a/stltovoxel/polygon_repair.py b/stltovoxel/polygon_repair.py
index 8eb9cf1..92c3784 100644
--- a/stltovoxel/polygon_repair.py
+++ b/stltovoxel/polygon_repair.py
@@ -1,6 +1,7 @@
 import numpy as np
 import math
 
+
 def find_polylines(segments):  # noqa: C901
     polylines = []
     segment_forward_dict = {}
@@ -94,7 +95,7 @@ def atan_sum(f1, f2):
     # atan2(atan_sum(f1, f2)) == atan2(f1) + atan2(f2)
     x1, y1 = f1
     x2, y2 = f2
-    return ( x1*x2 - y1*y2, y1*x2 + x1*y2)
+    return (x1*x2 - y1*y2, y1*x2 + x1*y2)
 
 
 def atan_neg(f1):
diff --git a/test/test_winding_query.py b/test/test_polygon_repair.py
similarity index 98%
rename from test/test_winding_query.py
rename to test/test_polygon_repair.py
index 9f03956..f52f76f 100644
--- a/test/test_winding_query.py
+++ b/test/test_polygon_repair.py
@@ -1,11 +1,10 @@
-import unittest
-import math
 import numpy as np
+import unittest
 
 from stltovoxel import polygon_repair
 
 
-class TestWindingQuery(unittest.TestCase):
+class TestPolygonRepair(unittest.TestCase):
     def tuples_almost_equal(self, actual, expected):
         for ac_val, exp_val in zip(actual, expected):
             self.assertAlmostEqual(ac_val, exp_val, 3, f"{actual} != {expected}")
@@ -68,7 +67,6 @@ def test_grad_90_norm(self):
         expected = polygon_repair.normalize((-1, -1))
         self.tuples_almost_equal(actual, expected)
 
-    
     def test_grad_90_norm2(self):
         segs = [((0, 0), (1, 0)), ((1, 0), (1, 1)), ((1, 1), (0, 1))]
         pos = (0, 0.5)
@@ -92,7 +90,7 @@ def test_grad_90_norm3(self):
         actual = polygon_repair.winding_contour(pos, segs)
         expected = polygon_repair.normalize((-1, -1))
         self.tuples_almost_equal(actual, expected)
-    
+
 
 if __name__ == '__main__':
     unittest.main()