diff --git a/interfaces/cython/cantera/composite.py b/interfaces/cython/cantera/composite.py
index 5ca7e12907..55cad77eb7 100644
--- a/interfaces/cython/cantera/composite.py
+++ b/interfaces/cython/cantera/composite.py
@@ -263,10 +263,10 @@ def __rmul__(self, other):
         return Quantity(self.phase, mass=self.mass * other, constant=self.constant)
 
     def __iadd__(self, other):
-        if (self._id != other._id):
+        if self._id != other._id:
             raise ValueError('Cannot add Quantities with different phase '
                 'definitions.')
-        assert(self.constant == other.constant)
+        assert self.constant == other.constant
         a1,b1 = getattr(self.phase, self.constant)
         a2,b2 = getattr(other.phase, self.constant)
         m = self.mass + other.mass
diff --git a/interfaces/cython/cantera/cti2yaml.py b/interfaces/cython/cantera/cti2yaml.py
index 8c44aba118..4ef33129db 100644
--- a/interfaces/cython/cantera/cti2yaml.py
+++ b/interfaces/cython/cantera/cti2yaml.py
@@ -1541,7 +1541,7 @@ def convert(filename=None, output_name=None, text=None):
 
     if filename is None and text is None:
         raise ValueError("One of filename or text must be specified")
-    elif (filename is not None and text is not None):
+    elif filename is not None and text is not None:
         raise ValueError("Only one of filename or text should be specified")
 
     if filename is not None:
diff --git a/interfaces/cython/cantera/examples/reactors/NonIdealShockTube.py b/interfaces/cython/cantera/examples/reactors/NonIdealShockTube.py
index 80645c7635..1dc9645a87 100644
--- a/interfaces/cython/cantera/examples/reactors/NonIdealShockTube.py
+++ b/interfaces/cython/cantera/examples/reactors/NonIdealShockTube.py
@@ -92,7 +92,7 @@ def ignitionDelay(states, species):
 t = 0
 
 counter = 1
-while(t < estimatedIgnitionDelayTime):
+while t < estimatedIgnitionDelayTime:
     t = reactorNetwork.step()
     if counter % 20 == 0:
         # We will save only every 20th value. Otherwise, this takes too long
@@ -130,7 +130,7 @@ def ignitionDelay(states, species):
 t = 0
 
 counter = 1
-while(t < estimatedIgnitionDelayTime):
+while t < estimatedIgnitionDelayTime:
     t = reactorNetwork.step()
     if counter % 20 == 0:
         # We will save only every 20th value. Otherwise, this takes too long