diff --git a/kuryr/tests/test_join.py b/kuryr/tests/test_join.py
index a4dadead..e2cca787 100644
--- a/kuryr/tests/test_join.py
+++ b/kuryr/tests/test_join.py
@@ -128,7 +128,7 @@ class TestKuryrJoinFailures(base.TestKuryrFailures):
         self.assertEqual(
             w_exceptions.BadRequest.code, response.status_code)
         decoded_json = jsonutils.loads(response.data)
-        self.assertTrue('Err' in decoded_json)
+        self.assertIn('Err', decoded_json)
         # TODO(tfukushima): Add the better error message validation.
-        self.assertTrue(invalid_docker_endpoint_id in decoded_json['Err'])
-        self.assertTrue('EndpointID' in decoded_json['Err'])
+        self.assertIn(invalid_docker_endpoint_id, decoded_json['Err'])
+        self.assertIn('EndpointID', decoded_json['Err'])
diff --git a/kuryr/tests/test_kuryr.py b/kuryr/tests/test_kuryr.py
index f58d5a2c..a38582a1 100644
--- a/kuryr/tests/test_kuryr.py
+++ b/kuryr/tests/test_kuryr.py
@@ -199,7 +199,7 @@ class TestKuryr(base.TestKuryrBase):
         # should be contained in the response.
         self.assertNotEqual(expected, decoded_json)
         app.logger.debug(decoded_json)
-        self.assertTrue('Address' in decoded_json['Interface'])
+        self.assertIn('Address', decoded_json['Interface'])
 
     def test_network_driver_create_endpoint_with_subnetpools(self):
         docker_network_id = hashlib.sha256(
@@ -310,8 +310,8 @@ class TestKuryr(base.TestKuryrBase):
         # Address and AddressIPv6, allocated by Neutron's IPAM automatically
         # should be contained in the response.
         self.assertNotEqual(expected, decoded_json)
-        self.assertTrue('Address' in decoded_json['Interface'])
-        self.assertTrue('AddressIPv6' in decoded_json['Interface'])
+        self.assertIn('Address', decoded_json['Interface'])
+        self.assertIn('AddressIPv6', decoded_json['Interface'])
 
     def test_network_driver_create_endpoint(self):
         docker_network_id = hashlib.sha256(
diff --git a/kuryr/tests/test_kuryr_endpoint.py b/kuryr/tests/test_kuryr_endpoint.py
index 6c9a41aa..e877599f 100644
--- a/kuryr/tests/test_kuryr_endpoint.py
+++ b/kuryr/tests/test_kuryr_endpoint.py
@@ -188,7 +188,7 @@ class TestKuryrEndpointCreateFailures(TestKuryrEndpointFailures):
 
         self.assertEqual(GivenException.status_code, response.status_code)
         decoded_json = jsonutils.loads(response.data)
-        self.assertTrue('Err' in decoded_json)
+        self.assertIn('Err', decoded_json)
         self.assertEqual({'Err': GivenException.message}, decoded_json)
 
     @ddt.data(exceptions.Unauthorized, exceptions.Forbidden,
@@ -227,7 +227,7 @@ class TestKuryrEndpointCreateFailures(TestKuryrEndpointFailures):
 
         self.assertEqual(GivenException.status_code, response.status_code)
         decoded_json = jsonutils.loads(response.data)
-        self.assertTrue('Err' in decoded_json)
+        self.assertIn('Err', decoded_json)
         self.assertEqual({'Err': GivenException.message}, decoded_json)
 
     def test_create_endpoint_bad_request(self):
@@ -240,10 +240,10 @@ class TestKuryrEndpointCreateFailures(TestKuryrEndpointFailures):
 
         self.assertEqual(400, response.status_code)
         decoded_json = jsonutils.loads(response.data)
-        self.assertTrue('Err' in decoded_json)
+        self.assertIn('Err', decoded_json)
         # TODO(tfukushima): Add the better error message validation.
-        self.assertTrue(invalid_docker_endpoint_id in decoded_json['Err'])
-        self.assertTrue('EndpointID' in decoded_json['Err'])
+        self.assertIn(invalid_docker_endpoint_id, decoded_json['Err'])
+        self.assertIn('EndpointID', decoded_json['Err'])
 
 
 @ddt.ddt
@@ -329,7 +329,7 @@ class TestKuryrEndpointDeleteFailures(TestKuryrEndpointFailures):
         else:
             self.assertEqual(GivenException.status_code, response.status_code)
             decoded_json = jsonutils.loads(response.data)
-            self.assertTrue('Err' in decoded_json)
+            self.assertIn('Err', decoded_json)
             self.assertEqual({'Err': GivenException.message}, decoded_json)
 
     @ddt.data(exceptions.Unauthorized, exceptions.NotFound,
@@ -359,7 +359,7 @@ class TestKuryrEndpointDeleteFailures(TestKuryrEndpointFailures):
 
         self.assertEqual(GivenException.status_code, response.status_code)
         decoded_json = jsonutils.loads(response.data)
-        self.assertTrue('Err' in decoded_json)
+        self.assertIn('Err', decoded_json)
         self.assertEqual({'Err': GivenException.message}, decoded_json)
 
     def test_delete_endpoint_bad_request(self):
@@ -372,7 +372,7 @@ class TestKuryrEndpointDeleteFailures(TestKuryrEndpointFailures):
 
         self.assertEqual(400, response.status_code)
         decoded_json = jsonutils.loads(response.data)
-        self.assertTrue('Err' in decoded_json)
+        self.assertIn('Err', decoded_json)
         # TODO(tfukushima): Add the better error message validation.
-        self.assertTrue(invalid_docker_endpoint_id in decoded_json['Err'])
-        self.assertTrue('EndpointID' in decoded_json['Err'])
+        self.assertIn(invalid_docker_endpoint_id, decoded_json['Err'])
+        self.assertIn('EndpointID', decoded_json['Err'])
diff --git a/kuryr/tests/test_kuryr_network.py b/kuryr/tests/test_kuryr_network.py
index 80647ae8..e7b50d55 100644
--- a/kuryr/tests/test_kuryr_network.py
+++ b/kuryr/tests/test_kuryr_network.py
@@ -57,7 +57,7 @@ class TestKuryrNetworkCreateFailures(base.TestKuryrFailures):
 
         self.assertEqual(401, response.status_code)
         decoded_json = jsonutils.loads(response.data)
-        self.assertTrue('Err' in decoded_json)
+        self.assertIn('Err', decoded_json)
         self.assertEqual(
             {'Err': exceptions.Unauthorized.message}, decoded_json)
 
@@ -67,10 +67,10 @@ class TestKuryrNetworkCreateFailures(base.TestKuryrFailures):
 
         self.assertEqual(400, response.status_code)
         decoded_json = jsonutils.loads(response.data)
-        self.assertTrue('Err' in decoded_json)
+        self.assertIn('Err', decoded_json)
         # TODO(tfukushima): Add the better error message validation.
-        self.assertTrue(invalid_docker_network_id in decoded_json['Err'])
-        self.assertTrue('NetworkID' in decoded_json['Err'])
+        self.assertIn(invalid_docker_network_id, decoded_json['Err'])
+        self.assertIn('NetworkID', decoded_json['Err'])
 
 
 @ddt
@@ -120,7 +120,7 @@ class TestKuryrNetworkDeleteFailures(base.TestKuryrFailures):
 
         self.assertEqual(GivenException.status_code, response.status_code)
         decoded_json = jsonutils.loads(response.data)
-        self.assertTrue('Err' in decoded_json)
+        self.assertIn('Err', decoded_json)
         self.assertEqual({'Err': GivenException.message}, decoded_json)
 
     def test_delete_network_bad_request(self):
@@ -130,6 +130,6 @@ class TestKuryrNetworkDeleteFailures(base.TestKuryrFailures):
 
         self.assertEqual(400, response.status_code)
         decoded_json = jsonutils.loads(response.data)
-        self.assertTrue('Err' in decoded_json)
-        self.assertTrue(invalid_docker_network_id in decoded_json['Err'])
-        self.assertTrue('NetworkID' in decoded_json['Err'])
+        self.assertIn('Err', decoded_json)
+        self.assertIn(invalid_docker_network_id, decoded_json['Err'])
+        self.assertIn('NetworkID', decoded_json['Err'])
diff --git a/kuryr/tests/test_utils.py b/kuryr/tests/test_utils.py
index 6b98f8bd..57090184 100644
--- a/kuryr/tests/test_utils.py
+++ b/kuryr/tests/test_utils.py
@@ -35,5 +35,5 @@ class TestKuryrUtils(base.TestKuryrBase):
             str(random.getrandbits(256))).hexdigest()
         generated_neutron_port_name = utils.get_neutron_port_name(
             fake_docker_endpoint_id)
-        self.assertTrue(utils.PORT_POSTFIX in generated_neutron_port_name)
-        self.assertTrue(fake_docker_endpoint_id in generated_neutron_port_name)
+        self.assertIn(utils.PORT_POSTFIX, generated_neutron_port_name)
+        self.assertIn(fake_docker_endpoint_id, generated_neutron_port_name)