diff --git a/python/lsst/afw/display/utils.py b/python/lsst/afw/display/utils.py
index 622c707cad..3fb2e865c4 100644
--- a/python/lsst/afw/display/utils.py
+++ b/python/lsst/afw/display/utils.py
@@ -205,7 +205,7 @@ def makeMosaic(self, images=None, display="deferToFrame", mode=None,
             if nx > self.nImage:
                 nx = self.nImage
 
-            assert(nx*ny >= self.nImage)
+            assert nx*ny >= self.nImage
         elif mode == "x":
             nx, ny = self.nImage, 1
         elif mode == "y":
diff --git a/python/lsst/afw/geom/_hpxUtils.py b/python/lsst/afw/geom/_hpxUtils.py
index 13cae5a62e..723f455513 100644
--- a/python/lsst/afw/geom/_hpxUtils.py
+++ b/python/lsst/afw/geom/_hpxUtils.py
@@ -424,7 +424,7 @@ def hash2i0(self, _hash):
         ij : `np.int64`
             Single value from which 2d coordinates can be extracted.
         """
-        assert((0xFFFFFFFF33333333 & np.int64(_hash)) == 0)
+        assert (0xFFFFFFFF33333333 & np.int64(_hash)) == 0
         return self.hash2ij(_hash)
 
     def ij2i(self, ij):
diff --git a/tests/test_chebyshevBoundedField.py b/tests/test_chebyshevBoundedField.py
index eacef726b0..db72edf238 100644
--- a/tests/test_chebyshevBoundedField.py
+++ b/tests/test_chebyshevBoundedField.py
@@ -177,7 +177,7 @@ def testMultiplyImageRaisesUnequalBBox(self):
         field = lsst.afw.math.ChebyshevBoundedField(self.image.getBBox(), coefficients)
         subBox = lsst.geom.Box2I(lsst.geom.Point2I(0, 3), lsst.geom.Point2I(3, 4))
         subImage = self.image.subset(subBox)
-        with(self.assertRaises(RuntimeError)):
+        with self.assertRaises(RuntimeError):
             field.multiplyImage(subImage)
 
     def testMultiplyImageOverlapSubImage(self):
diff --git a/tests/test_photoCalib.py b/tests/test_photoCalib.py
index 2bffdde7b7..d7fb9174f9 100644
--- a/tests/test_photoCalib.py
+++ b/tests/test_photoCalib.py
@@ -642,26 +642,26 @@ def testCalibrateImageNonConstantSubimage(self):
 
     def testNonPositiveMeans(self):
         # no negative calibrations
-        with(self.assertRaises(lsst.pex.exceptions.InvalidParameterError)):
+        with self.assertRaises(lsst.pex.exceptions.InvalidParameterError):
             lsst.afw.image.PhotoCalib(-1.0)
         # no negative errors
-        with(self.assertRaises(lsst.pex.exceptions.InvalidParameterError)):
+        with self.assertRaises(lsst.pex.exceptions.InvalidParameterError):
             lsst.afw.image.PhotoCalib(1.0, -1.0)
 
         # no negative calibration mean when computed from the bounded field
         negativeCalibration = lsst.afw.math.ChebyshevBoundedField(self.bbox,
                                                                   np.array([[-self.calibration]]))
-        with(self.assertRaises(lsst.pex.exceptions.InvalidParameterError)):
+        with self.assertRaises(lsst.pex.exceptions.InvalidParameterError):
             lsst.afw.image.PhotoCalib(negativeCalibration)
         # no negative calibration error
-        with(self.assertRaises(lsst.pex.exceptions.InvalidParameterError)):
+        with self.assertRaises(lsst.pex.exceptions.InvalidParameterError):
             lsst.afw.image.PhotoCalib(self.constantCalibration, -1.0)
 
         # no negative explicit calibration mean
-        with(self.assertRaises(lsst.pex.exceptions.InvalidParameterError)):
+        with self.assertRaises(lsst.pex.exceptions.InvalidParameterError):
             lsst.afw.image.PhotoCalib(-1.0, 0, self.constantCalibration, True)
         # no negative calibration error
-        with(self.assertRaises(lsst.pex.exceptions.InvalidParameterError)):
+        with self.assertRaises(lsst.pex.exceptions.InvalidParameterError):
             lsst.afw.image.PhotoCalib(1.0, -1.0, self.constantCalibration, True)
 
     def testPositiveErrors(self):
diff --git a/tests/test_spatialCell.py b/tests/test_spatialCell.py
index 69e2882f99..f8737a61e0 100644
--- a/tests/test_spatialCell.py
+++ b/tests/test_spatialCell.py
@@ -225,8 +225,8 @@ def testSpatialCell(self):
         dx, dy, sx, sy = 100, 100, 50, 50
         for x0, y0 in [(0, 0), (100, 100)]:
             # only works for tests where dx,dx is some multiple of sx,sy
-            assert(dx//sx == float(dx)/float(sx))
-            assert(dy//sy == float(dy)/float(sy))
+            assert dx//sx == float(dx)/float(sx)
+            assert dy//sy == float(dy)/float(sy)
 
             bbox = lsst.geom.Box2I(lsst.geom.Point2I(x0, y0),
                                    lsst.geom.Extent2I(dx, dy))