diff --git a/funlib/geometry/freezable.py b/funlib/geometry/freezable.py
index 5961a9e..fe77238 100644
--- a/funlib/geometry/freezable.py
+++ b/funlib/geometry/freezable.py
@@ -1,5 +1,4 @@
 class Freezable(object):
-
     __isfrozen = False
 
     def __setattr__(self, key, value):
diff --git a/tests/test_coordinate.py b/tests/test_coordinate.py
index ceaeb1e..1ea5852 100644
--- a/tests/test_coordinate.py
+++ b/tests/test_coordinate.py
@@ -4,7 +4,6 @@
 
 
 def test_constructor():
-
     # construct from tuples, lists, and generators
 
     assert Coordinate(0) == (0,)
@@ -21,7 +20,6 @@ def test_constructor():
 
 
 def test_arithmetic():
-
     a = Coordinate((1, 2, 3))
     b = Coordinate((4, 5, 6))
     c = Coordinate((7, 8))
@@ -80,12 +78,11 @@ def test_powers():
     a = Coordinate(2, 3, 0)
     b = Coordinate(2, 0, 1)
 
-    assert a ** b == (4, 1, 0)
-    assert a ** 2 == (4, 9, 0)
+    assert a**b == (4, 1, 0)
+    assert a**2 == (4, 9, 0)
 
 
 def test_none():
-
     a = Coordinate((None, 1, 2))
     b = Coordinate((3, 4, None))
 
diff --git a/tests/test_roi.py b/tests/test_roi.py
index 7acfbd4..345cad6 100644
--- a/tests/test_roi.py
+++ b/tests/test_roi.py
@@ -4,7 +4,6 @@
 
 
 def test_squeeze():
-
     r = Roi((1, 2, 3), (4, 5, 6))
     assert r.dims == 3
     r = r.squeeze(1)
@@ -14,7 +13,6 @@ def test_squeeze():
 
 
 def test_shape():
-
     r = Roi((0,), (1,))
     assert r.size == 1
     assert r.empty is False
@@ -61,7 +59,6 @@ def test_shape():
 
 
 def test_operators():
-
     a = Roi((0, 0, 0), (100, 100, 100))
     b = Roi((50, 50, 50), (100, 100, 100))
 
@@ -112,7 +109,6 @@ def test_operators():
 
 
 def test_snap():
-
     a = Roi((1,), (7,))
 
     assert a.snap_to_grid(Coord(2), "grow") == Roi((0,), (8,))
@@ -140,7 +136,6 @@ def test_snap():
 
 
 def test_arithmetic():
-
     a = Roi((1, None), (7, None))
 
     assert a + 1 == Roi((2, None), (7, None))