diff --git a/doc/source/conf.py b/doc/source/conf.py
index f11d96a..b9e22b5 100644
--- a/doc/source/conf.py
+++ b/doc/source/conf.py
@@ -155,8 +155,7 @@
 git_cmd = ["git", "log", "--pretty=format:'%ad, commit %h'", "--date=local",
    "-n1"]
 try:
-    html_last_updated_fmt = str(
-        subprocess.Popen(git_cmd, stdout=subprocess.PIPE).communicate()[0])
+    html_last_updated_fmt = subprocess.check_output(git_cmd).decode('utf-8')
 except Exception:
     warnings.warn('Cannot get last updated time from git repository. '
                   'Not setting "html_last_updated_fmt".')
diff --git a/releasenotes/notes/prevent-error-in-parse-resp-when-nullable-list-9898cd0f22180986.yaml b/releasenotes/notes/prevent-error-in-parse-resp-when-nullable-list-9898cd0f22180986.yaml
new file mode 100644
index 0000000..afb6006
--- /dev/null
+++ b/releasenotes/notes/prevent-error-in-parse-resp-when-nullable-list-9898cd0f22180986.yaml
@@ -0,0 +1,6 @@
+---
+fixes:
+  - |
+    When receiving nullable list as a response body, tempest.lib
+    rest_client module raised an exception without valid json
+    deserialization. A new release fixes this bug.
diff --git a/tempest/api/compute/admin/test_flavors_access.py b/tempest/api/compute/admin/test_flavors_access.py
index 5a38acc..2c236ec 100644
--- a/tempest/api/compute/admin/test_flavors_access.py
+++ b/tempest/api/compute/admin/test_flavors_access.py
@@ -50,7 +50,7 @@
 
         flavor_access = (self.admin_flavors_client.list_flavor_access(
                          flavor['id'])['flavor_access'])
-        self.assertEqual(len(flavor_access), 0, str(flavor_access))
+        self.assertEmpty(flavor_access)
 
     @decorators.idempotent_id('59e622f6-bdf6-45e3-8ba8-fedad905a6b4')
     def test_flavor_access_add_remove(self):
diff --git a/tempest/api/compute/admin/test_hosts.py b/tempest/api/compute/admin/test_hosts.py
index 5b3bb2c..0e1e7ed 100644
--- a/tempest/api/compute/admin/test_hosts.py
+++ b/tempest/api/compute/admin/test_hosts.py
@@ -36,7 +36,7 @@
         hosts = self.client.list_hosts()['hosts']
         host = hosts[0]
         hosts = self.client.list_hosts(zone=host['zone'])['hosts']
-        self.assertGreaterEqual(len(hosts), 1)
+        self.assertNotEmpty(hosts)
         self.assertIn(host, hosts)
 
     @decorators.idempotent_id('9af3c171-fbf4-4150-a624-22109733c2a6')
@@ -58,12 +58,12 @@
         hosts = self.client.list_hosts()['hosts']
 
         hosts = [host for host in hosts if host['service'] == 'compute']
-        self.assertGreaterEqual(len(hosts), 1)
+        self.assertNotEmpty(hosts)
 
         for host in hosts:
             hostname = host['host_name']
             resources = self.client.show_host(hostname)['host']
-            self.assertGreaterEqual(len(resources), 1)
+            self.assertNotEmpty(resources)
             host_resource = resources[0]['resource']
             self.assertIsNotNone(host_resource)
             self.assertIsNotNone(host_resource['cpu'])
diff --git a/tempest/api/compute/admin/test_networks.py b/tempest/api/compute/admin/test_networks.py
index 0ea0a78..acb0d90 100644
--- a/tempest/api/compute/admin/test_networks.py
+++ b/tempest/api/compute/admin/test_networks.py
@@ -62,4 +62,4 @@
             self.assertIn(configured_network, [x['label'] for x in networks])
         else:
             network_labels = [x['label'] for x in networks]
-            self.assertGreaterEqual(len(network_labels), 1)
+            self.assertNotEmpty(network_labels)
diff --git a/tempest/api/compute/servers/test_server_addresses.py b/tempest/api/compute/servers/test_server_addresses.py
index 92b1ff1..022ceba 100644
--- a/tempest/api/compute/servers/test_server_addresses.py
+++ b/tempest/api/compute/servers/test_server_addresses.py
@@ -48,9 +48,9 @@
 
         # We do not know the exact network configuration, but an instance
         # should at least have a single public or private address
-        self.assertGreaterEqual(len(addresses), 1)
+        self.assertNotEmpty(addresses)
         for network_addresses in addresses.values():
-            self.assertGreaterEqual(len(network_addresses), 1)
+            self.assertNotEmpty(network_addresses)
             for address in network_addresses:
                 self.assertTrue(address['addr'])
                 self.assertTrue(address['version'])
diff --git a/tempest/api/identity/admin/v2/test_roles_negative.py b/tempest/api/identity/admin/v2/test_roles_negative.py
index 86d06e2..f3b7494 100644
--- a/tempest/api/identity/admin/v2/test_roles_negative.py
+++ b/tempest/api/identity/admin/v2/test_roles_negative.py
@@ -143,7 +143,7 @@
     @decorators.idempotent_id('99b297f6-2b5d-47c7-97a9-8b6bb4f91042')
     def test_assign_user_role_for_non_existent_role(self):
         # Attempt to assign a non existent role to user should fail
-        (user, tenant, role) = self._get_role_params()
+        (user, tenant, _) = self._get_role_params()
         non_existent_role = data_utils.rand_uuid_hex()
         self.assertRaises(lib_exc.NotFound,
                           self.roles_client.create_user_role_on_project,
@@ -153,7 +153,7 @@
     @decorators.idempotent_id('b2285aaa-9e76-4704-93a9-7a8acd0a6c8f')
     def test_assign_user_role_for_non_existent_tenant(self):
         # Attempt to assign a role on a non existent tenant should fail
-        (user, tenant, role) = self._get_role_params()
+        (user, _, role) = self._get_role_params()
         non_existent_tenant = data_utils.rand_uuid_hex()
         self.assertRaises(lib_exc.NotFound,
                           self.roles_client.create_user_role_on_project,
@@ -244,7 +244,7 @@
     @decorators.idempotent_id('682adfb2-fd5f-4b0a-a9ca-322e9bebb907')
     def test_list_user_roles_request_without_token(self):
         # Request to list user's roles without a valid token should fail
-        (user, tenant, role) = self._get_role_params()
+        (user, tenant, _) = self._get_role_params()
         token = self.client.auth_provider.get_token()
         self.client.delete_token(token)
         try:
diff --git a/tempest/api/identity/admin/v3/test_default_project_id.py b/tempest/api/identity/admin/v3/test_default_project_id.py
index ac2faa9..302a0e5 100644
--- a/tempest/api/identity/admin/v3/test_default_project_id.py
+++ b/tempest/api/identity/admin/v3/test_default_project_id.py
@@ -79,7 +79,7 @@
         admin_client = clients.Manager(credentials=creds)
 
         # verify the user's token and see that it is scoped to the project
-        token, auth_data = admin_client.auth_provider.get_auth()
+        token, _ = admin_client.auth_provider.get_auth()
         result = admin_client.identity_v3_client.show_token(token)['token']
         self.assertEqual(result['project']['domain']['id'], dom_id)
         self.assertEqual(result['project']['id'], proj_id)
diff --git a/tempest/api/network/admin/test_agent_management.py b/tempest/api/network/admin/test_agent_management.py
index 6389489..7304db9 100644
--- a/tempest/api/network/admin/test_agent_management.py
+++ b/tempest/api/network/admin/test_agent_management.py
@@ -49,7 +49,7 @@
     @decorators.idempotent_id('e335be47-b9a1-46fd-be30-0874c0b751e6')
     def test_list_agents_non_admin(self):
         body = self.agents_client.list_agents()
-        self.assertEqual(len(body["agents"]), 0)
+        self.assertEmpty(body["agents"])
 
     @decorators.idempotent_id('869bc8e8-0fda-4a30-9b71-f8a7cf58ca9f')
     def test_show_agent(self):
diff --git a/tempest/api/network/admin/test_metering_extensions.py b/tempest/api/network/admin/test_metering_extensions.py
index 2b789e7..21a7ab4 100644
--- a/tempest/api/network/admin/test_metering_extensions.py
+++ b/tempest/api/network/admin/test_metering_extensions.py
@@ -74,7 +74,7 @@
         # Asserting that the label is not found in list after deletion
         labels = self.admin_metering_labels_client.list_metering_labels(
             id=metering_label_id)
-        self.assertEqual(len(labels['metering_labels']), 0)
+        self.assertEmpty(labels['metering_labels'])
 
     def _delete_metering_label_rule(self, metering_label_rule_id):
         client = self.admin_metering_label_rules_client
diff --git a/tempest/api/network/admin/test_routers.py b/tempest/api/network/admin/test_routers.py
index ec8d260..07c4157 100644
--- a/tempest/api/network/admin/test_routers.py
+++ b/tempest/api/network/admin/test_routers.py
@@ -134,7 +134,7 @@
         self.assertEqual(len(list_body['ports']), 1)
         gw_port = list_body['ports'][0]
         fixed_ips = gw_port['fixed_ips']
-        self.assertGreaterEqual(len(fixed_ips), 1)
+        self.assertNotEmpty(fixed_ips)
         # Assert that all of the IPs from the router gateway port
         # are allocated from a valid public subnet.
         public_net_body = self.admin_networks_client.show_network(
diff --git a/tempest/api/network/test_routers.py b/tempest/api/network/test_routers.py
index d78cd1e..128544b 100644
--- a/tempest/api/network/test_routers.py
+++ b/tempest/api/network/test_routers.py
@@ -156,7 +156,7 @@
         self.assertEqual(len(list_body['ports']), 1)
         gw_port = list_body['ports'][0]
         fixed_ips = gw_port['fixed_ips']
-        self.assertGreaterEqual(len(fixed_ips), 1)
+        self.assertNotEmpty(fixed_ips)
         # Assert that all of the IPs from the router gateway port
         # are allocated from a valid public subnet.
         public_net_body = self.admin_networks_client.show_network(
diff --git a/tempest/api/network/test_security_groups.py b/tempest/api/network/test_security_groups.py
index 0d5e230..a121864 100644
--- a/tempest/api/network/test_security_groups.py
+++ b/tempest/api/network/test_security_groups.py
@@ -83,7 +83,7 @@
     @decorators.attr(type='smoke')
     @decorators.idempotent_id('bfd128e5-3c92-44b6-9d66-7fe29d22c802')
     def test_create_list_update_show_delete_security_group(self):
-        group_create_body, name = self._create_security_group()
+        group_create_body, _ = self._create_security_group()
 
         # List security groups and verify if created group is there in response
         list_body = self.security_groups_client.list_security_groups()
diff --git a/tempest/api/object_storage/base.py b/tempest/api/object_storage/base.py
index 2bac8d3..13614cb 100644
--- a/tempest/api/object_storage/base.py
+++ b/tempest/api/object_storage/base.py
@@ -43,8 +43,7 @@
     for cont in containers:
         try:
             params = {'limit': 9999, 'format': 'json'}
-            resp, objlist = container_client.list_container_contents(
-                cont, params)
+            _, objlist = container_client.list_container_contents(cont, params)
             # delete every object in the container
             for obj in objlist:
                 test_utils.call_and_ignore_notfound_exc(
diff --git a/tempest/api/object_storage/test_account_bulk.py b/tempest/api/object_storage/test_account_bulk.py
index 0a72d75..e765414 100644
--- a/tempest/api/object_storage/test_account_bulk.py
+++ b/tempest/api/object_storage/test_account_bulk.py
@@ -112,7 +112,7 @@
         self._upload_archive(filepath)
 
         data = '%s/%s\n%s' % (container_name, object_name, container_name)
-        resp, body = self.bulk_client.delete_bulk_data(data=data)
+        resp, _ = self.bulk_client.delete_bulk_data(data=data)
 
         # When deleting multiple files using the bulk operation, the response
         # does not contain 'content-length' header. This is the special case,
@@ -138,7 +138,7 @@
 
         data = '%s/%s\n%s' % (container_name, object_name, container_name)
 
-        resp, body = self.bulk_client.delete_bulk_data_with_post(data=data)
+        resp, _ = self.bulk_client.delete_bulk_data_with_post(data=data)
 
         # When deleting multiple files using the bulk operation, the response
         # does not contain 'content-length' header. This is the special case,
diff --git a/tempest/api/object_storage/test_account_services.py b/tempest/api/object_storage/test_account_services.py
index e54b6e7..9e62046 100644
--- a/tempest/api/object_storage/test_account_services.py
+++ b/tempest/api/object_storage/test_account_services.py
@@ -101,7 +101,7 @@
         # Check only the format of common headers with custom matcher
         self.assertThat(resp, custom_matchers.AreAllWellFormatted())
 
-        self.assertEqual(len(container_list), 0)
+        self.assertEmpty(container_list)
 
     @decorators.idempotent_id('1c7efa35-e8a2-4b0b-b5ff-862c7fd83704')
     def test_list_containers_with_format_json(self):
@@ -135,7 +135,7 @@
         not CONF.object_storage_feature_enabled.discoverability,
         'Discoverability function is disabled')
     def test_list_extensions(self):
-        resp, extensions = self.capabilities_client.list_capabilities()
+        resp, _ = self.capabilities_client.list_capabilities()
 
         self.assertThat(resp, custom_matchers.AreAllWellFormatted())
 
@@ -162,7 +162,7 @@
             self.account_client.list_account_containers(params=params)
         self.assertHeaders(resp, 'Account', 'GET')
 
-        self.assertEqual(len(container_list), 0)
+        self.assertEmpty(container_list)
 
         params = {'marker': self.containers[self.containers_count // 2]}
         resp, container_list = \
@@ -182,7 +182,7 @@
         resp, container_list = \
             self.account_client.list_account_containers(params=params)
         self.assertHeaders(resp, 'Account', 'GET')
-        self.assertEqual(len(container_list), 0)
+        self.assertEmpty(container_list)
 
         params = {'end_marker': self.containers[self.containers_count // 2]}
         resp, container_list = \
@@ -297,7 +297,7 @@
             create_update_metadata=metadata)
         self.assertHeaders(resp, 'Account', 'POST')
 
-        resp, body = self.account_client.list_account_metadata()
+        resp, _ = self.account_client.list_account_metadata()
         self.assertIn('x-account-meta-test-account-meta1', resp)
         self.assertEqual(resp['x-account-meta-test-account-meta1'],
                          metadata['test-account-meta1'])
@@ -352,7 +352,7 @@
         self.account_client.create_update_or_delete_account_metadata(
             create_update_metadata=metadata_1)
         metadata_2 = {'test-account-meta2': 'Meta2'}
-        resp, body = (
+        resp, _ = (
             self.account_client.create_update_or_delete_account_metadata(
                 create_update_metadata=metadata_2,
                 delete_metadata=metadata_1))
diff --git a/tempest/api/object_storage/test_container_acl.py b/tempest/api/object_storage/test_container_acl.py
index d4e5ec5..4b66ebf 100644
--- a/tempest/api/object_storage/test_container_acl.py
+++ b/tempest/api/object_storage/test_container_acl.py
@@ -41,10 +41,10 @@
         tenant_name = self.os_roles_operator_alt.credentials.tenant_name
         username = self.os_roles_operator_alt.credentials.username
         cont_headers = {'X-Container-Read': tenant_name + ':' + username}
-        resp_meta, body = self.os_roles_operator.container_client.\
-            update_container_metadata(
+        resp_meta, _ = (
+            self.os_roles_operator.container_client.update_container_metadata(
                 self.container_name, metadata=cont_headers,
-                metadata_prefix='')
+                metadata_prefix=''))
         self.assertHeaders(resp_meta, 'Container', 'POST')
         # create object
         object_name = data_utils.rand_name(name='Object')
@@ -68,10 +68,10 @@
         tenant_name = self.os_roles_operator_alt.credentials.tenant_name
         username = self.os_roles_operator_alt.credentials.username
         cont_headers = {'X-Container-Write': tenant_name + ':' + username}
-        resp_meta, body = self.os_roles_operator.container_client.\
-            update_container_metadata(self.container_name,
-                                      metadata=cont_headers,
-                                      metadata_prefix='')
+        resp_meta, _ = (
+            self.os_roles_operator.container_client.update_container_metadata(
+                self.container_name, metadata=cont_headers,
+                metadata_prefix=''))
         self.assertHeaders(resp_meta, 'Container', 'POST')
         # set alternative authentication data; cannot simply use the
         # other object client.
diff --git a/tempest/api/object_storage/test_container_acl_negative.py b/tempest/api/object_storage/test_container_acl_negative.py
index 9c9d821..655626c 100644
--- a/tempest/api/object_storage/test_container_acl_negative.py
+++ b/tempest/api/object_storage/test_container_acl_negative.py
@@ -65,8 +65,8 @@
     def test_delete_object_without_using_creds(self):
         # create object
         object_name = data_utils.rand_name(name='Object')
-        resp, _ = self.object_client.create_object(self.container_name,
-                                                   object_name, 'data')
+        self.object_client.create_object(self.container_name, object_name,
+                                         'data')
         # trying to delete object with empty headers
         # X-Auth-Token is not provided
         self.object_client.auth_provider.set_alt_auth_data(
@@ -134,7 +134,7 @@
         # attempt to read object using non-authorized user
         # update X-Container-Read metadata ACL
         cont_headers = {'X-Container-Read': 'badtenant:baduser'}
-        resp_meta, body = self.container_client.update_container_metadata(
+        resp_meta, _ = self.container_client.update_container_metadata(
             self.container_name, metadata=cont_headers,
             metadata_prefix='')
         self.assertHeaders(resp_meta, 'Container', 'POST')
@@ -158,7 +158,7 @@
         # attempt to write object using non-authorized user
         # update X-Container-Write metadata ACL
         cont_headers = {'X-Container-Write': 'badtenant:baduser'}
-        resp_meta, body = self.container_client.update_container_metadata(
+        resp_meta, _ = self.container_client.update_container_metadata(
             self.container_name, metadata=cont_headers,
             metadata_prefix='')
         self.assertHeaders(resp_meta, 'Container', 'POST')
@@ -183,7 +183,7 @@
         cont_headers = {'X-Container-Read':
                         tenant_name + ':' + username,
                         'X-Container-Write': ''}
-        resp_meta, body = self.container_client.update_container_metadata(
+        resp_meta, _ = self.container_client.update_container_metadata(
             self.container_name, metadata=cont_headers,
             metadata_prefix='')
         self.assertHeaders(resp_meta, 'Container', 'POST')
@@ -208,7 +208,7 @@
         cont_headers = {'X-Container-Read':
                         tenant_name + ':' + username,
                         'X-Container-Write': ''}
-        resp_meta, body = self.container_client.update_container_metadata(
+        resp_meta, _ = self.container_client.update_container_metadata(
             self.container_name, metadata=cont_headers,
             metadata_prefix='')
         self.assertHeaders(resp_meta, 'Container', 'POST')
diff --git a/tempest/api/object_storage/test_container_services.py b/tempest/api/object_storage/test_container_services.py
index 2b5692d..76fe8d4 100644
--- a/tempest/api/object_storage/test_container_services.py
+++ b/tempest/api/object_storage/test_container_services.py
@@ -27,7 +27,7 @@
     @decorators.idempotent_id('92139d73-7819-4db1-85f8-3f2f22a8d91f')
     def test_create_container(self):
         container_name = data_utils.rand_name(name='TestContainer')
-        resp, body = self.container_client.create_container(container_name)
+        resp, _ = self.container_client.create_container(container_name)
         self.containers.append(container_name)
         self.assertHeaders(resp, 'Container', 'PUT')
 
diff --git a/tempest/api/object_storage/test_container_staticweb.py b/tempest/api/object_storage/test_container_staticweb.py
index 9e01c26..378061a 100644
--- a/tempest/api/object_storage/test_container_staticweb.py
+++ b/tempest/api/object_storage/test_container_staticweb.py
@@ -124,9 +124,8 @@
 
         # test GET on http://account_url/container_name
         # we should retrieve a listing of objects
-        resp, body = self.account_client.request("GET",
-                                                 self.container_name,
-                                                 headers={})
+        _, body = self.account_client.request("GET", self.container_name,
+                                              headers={})
         self.assertIn(self.object_name, body.decode())
         css = '<link rel="stylesheet" type="text/css" href="listings.css" />'
         self.assertIn(css, body.decode())
diff --git a/tempest/api/object_storage/test_container_sync.py b/tempest/api/object_storage/test_container_sync.py
index 3c11a51..4cb1914 100644
--- a/tempest/api/object_storage/test_container_sync.py
+++ b/tempest/api/object_storage/test_container_sync.py
@@ -90,8 +90,7 @@
             cont_client = [self.clients[c][0] for c in cont]
             obj_client = [self.clients[c][1] for c in cont]
             headers = make_headers(cont[1], cont_client[1])
-            resp, body = \
-                cont_client[0].put(str(cont[0]), body=None, headers=headers)
+            cont_client[0].put(str(cont[0]), body=None, headers=headers)
             # create object in container
             object_name = data_utils.rand_name(name='TestSyncObject')
             data = object_name[::-1].encode()  # Raw data, we need bytes
diff --git a/tempest/api/object_storage/test_object_expiry.py b/tempest/api/object_storage/test_object_expiry.py
index 7768d23..ed1be90 100644
--- a/tempest/api/object_storage/test_object_expiry.py
+++ b/tempest/api/object_storage/test_object_expiry.py
@@ -54,8 +54,8 @@
         # actually expire, so figure out how many secs in the future that is.
         sleepy_time = int(resp['x-delete-at']) - int(time.time())
         sleepy_time = sleepy_time if sleepy_time > 0 else 0
-        resp, body = self.object_client.get_object(self.container_name,
-                                                   self.object_name)
+        resp, _ = self.object_client.get_object(self.container_name,
+                                                self.object_name)
         self.assertHeaders(resp, 'Object', 'GET')
         self.assertIn('x-delete-at', resp)
 
diff --git a/tempest/api/object_storage/test_object_services.py b/tempest/api/object_storage/test_object_services.py
index 21ea6ae..b29a77f 100644
--- a/tempest/api/object_storage/test_object_services.py
+++ b/tempest/api/object_storage/test_object_services.py
@@ -48,7 +48,7 @@
         data_segments = [data + str(i) for i in range(segments)]
         # uploading segments
         for i in range(segments):
-            resp, _ = self.object_client.create_object_segments(
+            self.object_client.create_object_segments(
                 self.container_name, object_name, i, data_segments[i])
 
         return object_name, data_segments
@@ -184,7 +184,7 @@
         # create object with transfer_encoding
         object_name = data_utils.rand_name(name='TestObject')
         data = data_utils.random_bytes(1024)
-        status, _, resp_headers = self.object_client.put_object_with_chunk(
+        _, _, resp_headers = self.object_client.put_object_with_chunk(
             container=self.container_name,
             name=object_name,
             contents=data_utils.chunkify(data, 512)
@@ -394,7 +394,7 @@
         # update object metadata with x_object_manifest
 
         # uploading segments
-        object_name, data_segments = self._upload_segments()
+        object_name, _ = self._upload_segments()
         # creating a manifest file
         data_empty = ''
         self.object_client.create_object(self.container_name,
@@ -414,7 +414,7 @@
             self.container_name,
             object_name)
         self.assertIn('x-object-manifest', resp)
-        self.assertNotEqual(len(resp['x-object-manifest']), 0)
+        self.assertNotEmpty(resp['x-object-manifest'])
 
     @decorators.idempotent_id('0dbbe89c-6811-4d84-a2df-eca2bdd40c0e')
     def test_update_object_metadata_with_x_object_metakey(self):
@@ -494,7 +494,7 @@
         # get object metadata with x_object_manifest
 
         # uploading segments
-        object_name, data_segments = self._upload_segments()
+        object_name, _ = self._upload_segments()
         # creating a manifest file
         object_prefix = '%s/%s' % (self.container_name, object_name)
         metadata = {'X-Object-Manifest': object_prefix}
@@ -520,11 +520,11 @@
         self.assertTrue(resp['etag'].startswith('\"'))
         self.assertTrue(resp['etag'].endswith('\"'))
         self.assertTrue(resp['etag'].strip('\"').isalnum())
-        self.assertTrue(re.match("^\d+\.?\d*\Z", resp['x-timestamp']))
-        self.assertNotEqual(len(resp['content-type']), 0)
+        self.assertTrue(re.match(r"^\d+\.?\d*\Z", resp['x-timestamp']))
+        self.assertNotEmpty(resp['content-type'])
         self.assertTrue(re.match("^tx[0-9a-f]{21}-[0-9a-f]{10}.*",
                                  resp['x-trans-id']))
-        self.assertNotEqual(len(resp['date']), 0)
+        self.assertNotEmpty(resp['date'])
         self.assertEqual(resp['accept-ranges'], 'bytes')
         self.assertEqual(resp['x-object-manifest'],
                          '%s/%s' % (self.container_name, object_name))
@@ -612,11 +612,11 @@
         self.assertTrue(resp['etag'].startswith('\"'))
         self.assertTrue(resp['etag'].endswith('\"'))
         self.assertTrue(resp['etag'].strip('\"').isalnum())
-        self.assertTrue(re.match("^\d+\.?\d*\Z", resp['x-timestamp']))
-        self.assertNotEqual(len(resp['content-type']), 0)
+        self.assertTrue(re.match(r"^\d+\.?\d*\Z", resp['x-timestamp']))
+        self.assertNotEmpty(resp['content-type'])
         self.assertTrue(re.match("^tx[0-9a-f]{21}-[0-9a-f]{10}.*",
                                  resp['x-trans-id']))
-        self.assertNotEqual(len(resp['date']), 0)
+        self.assertNotEmpty(resp['date'])
         self.assertEqual(resp['accept-ranges'], 'bytes')
         self.assertEqual(resp['x-object-manifest'],
                          '%s/%s' % (self.container_name, object_name))
@@ -955,7 +955,7 @@
         local_data = "something different"
         md5 = hashlib.md5(local_data.encode()).hexdigest()
         headers = {'If-None-Match': md5}
-        resp, body = self.object_client.get(url, headers=headers)
+        resp, _ = self.object_client.get(url, headers=headers)
         self.assertHeaders(resp, 'Object', 'GET')
 
 
diff --git a/tempest/api/object_storage/test_object_slo.py b/tempest/api/object_storage/test_object_slo.py
index 085ad13..894e42d 100644
--- a/tempest/api/object_storage/test_object_slo.py
+++ b/tempest/api/object_storage/test_object_slo.py
@@ -127,7 +127,7 @@
         # list static large object metadata using multipart manifest
         object_name = self._create_large_object()
 
-        resp, body = self.object_client.list_object_metadata(
+        resp, _ = self.object_client.list_object_metadata(
             self.container_name,
             object_name)
 
@@ -155,7 +155,7 @@
         object_name = self._create_large_object()
 
         params_del = {'multipart-manifest': 'delete'}
-        resp, body = self.object_client.delete_object(
+        resp, _ = self.object_client.delete_object(
             self.container_name,
             object_name,
             params=params_del)
diff --git a/tempest/api/object_storage/test_object_temp_url.py b/tempest/api/object_storage/test_object_temp_url.py
index 4b506f8..91bc677 100644
--- a/tempest/api/object_storage/test_object_temp_url.py
+++ b/tempest/api/object_storage/test_object_temp_url.py
@@ -128,7 +128,7 @@
         url = self._get_temp_url(self.container_name,
                                  self.object_name, "GET",
                                  expires, key2)
-        resp, body = self.object_client.get(url)
+        _, body = self.object_client.get(url)
         self.assertEqual(body, self.content)
 
     @decorators.idempotent_id('9b08dade-3571-4152-8a4f-a4f2a873a735')
@@ -168,7 +168,7 @@
                                  expires, self.key)
 
         # Testing a HEAD on this Temp URL
-        resp, body = self.object_client.head(url)
+        resp, _ = self.object_client.head(url)
         self.assertHeaders(resp, 'Object', 'HEAD')
 
     @decorators.idempotent_id('9d9cfd90-708b-465d-802c-e4a8090b823d')
diff --git a/tempest/api/object_storage/test_object_temp_url_negative.py b/tempest/api/object_storage/test_object_temp_url_negative.py
index f4d63fd..3edaa86 100644
--- a/tempest/api/object_storage/test_object_temp_url_negative.py
+++ b/tempest/api/object_storage/test_object_temp_url_negative.py
@@ -46,7 +46,7 @@
 
     @classmethod
     def resource_cleanup(cls):
-        resp, _ = cls.account_client.create_update_or_delete_account_metadata(
+        cls.account_client.create_update_or_delete_account_metadata(
             delete_metadata=cls.metadata)
 
         cls.delete_containers()
diff --git a/tempest/api/volume/admin/test_snapshot_manage.py b/tempest/api/volume/admin/test_snapshot_manage.py
index a2d5fb1..9f96194 100644
--- a/tempest/api/volume/admin/test_snapshot_manage.py
+++ b/tempest/api/volume/admin/test_snapshot_manage.py
@@ -18,6 +18,7 @@
 from tempest.api.volume import base
 from tempest.common import waiters
 from tempest import config
+from tempest.lib.common.utils import data_utils
 from tempest.lib import decorators
 
 CONF = config.CONF
@@ -56,11 +57,19 @@
         # Verify snapshot does not exist in snapshot list
         self.assertNotIn(snapshot['id'], snapshot_list)
 
+        name = data_utils.rand_name(self.__class__.__name__ +
+                                    '-Managed-Snapshot')
+        description = data_utils.rand_name(self.__class__.__name__ +
+                                           '-Managed-Snapshot-Description')
+        metadata = {"manage-snap-meta1": "value1",
+                    "manage-snap-meta2": "value2",
+                    "manage-snap-meta3": "value3"}
+
         # Manage the snapshot
         snapshot_ref = '_snapshot-%s' % snapshot['id']
         new_snapshot = self.admin_snapshot_manage_client.manage_snapshot(
-            volume_id=volume['id'],
-            ref={'source-name': snapshot_ref})['snapshot']
+            volume_id=volume['id'], ref={'source-name': snapshot_ref},
+            name=name, description=description, metadata=metadata)['snapshot']
         self.addCleanup(self.delete_snapshot, new_snapshot['id'],
                         self.admin_snapshots_client)
 
@@ -70,4 +79,10 @@
                                                 'available')
 
         # Verify the managed snapshot has the expected parent volume
-        self.assertEqual(new_snapshot['volume_id'], volume['id'])
+        # and the expected field values.
+        new_snap_info = self.admin_snapshots_client.show_snapshot(
+            new_snapshot['id'])['snapshot']
+        self.assertEqual(volume['id'], new_snap_info['volume_id'])
+        self.assertEqual(name, new_snap_info['name'])
+        self.assertEqual(description, new_snap_info['description'])
+        self.assertEqual(metadata, new_snap_info['metadata'])
diff --git a/tempest/api/volume/admin/test_volumes_actions.py b/tempest/api/volume/admin/test_volumes_actions.py
index acff7cd..b81a477 100644
--- a/tempest/api/volume/admin/test_volumes_actions.py
+++ b/tempest/api/volume/admin/test_volumes_actions.py
@@ -70,7 +70,7 @@
     @test.services('compute')
     def test_force_detach_volume(self):
         # Create a server and a volume
-        server_id = self.create_server(wait_until='ACTIVE')['id']
+        server_id = self.create_server()['id']
         volume_id = self.create_volume()['id']
 
         # Attach volume
diff --git a/tempest/api/volume/base.py b/tempest/api/volume/base.py
index eace92d..8d66156 100644
--- a/tempest/api/volume/base.py
+++ b/tempest/api/volume/base.py
@@ -217,7 +217,7 @@
                 cls.snapshots_client.wait_for_resource_deletion,
                 snapshot)
 
-    def create_server(self, **kwargs):
+    def create_server(self, wait_until='ACTIVE', **kwargs):
         name = kwargs.pop(
             'name',
             data_utils.rand_name(self.__class__.__name__ + '-instance'))
@@ -227,6 +227,7 @@
             self.os_primary,
             tenant_network=tenant_network,
             name=name,
+            wait_until=wait_until,
             **kwargs)
 
         self.addCleanup(test_utils.call_and_ignore_notfound_exc,
diff --git a/tempest/api/volume/test_volume_transfers.py b/tempest/api/volume/test_volume_transfers.py
index 5a192ac..2c13a3c 100644
--- a/tempest/api/volume/test_volume_transfers.py
+++ b/tempest/api/volume/test_volume_transfers.py
@@ -13,8 +13,6 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
-from testtools import matchers
-
 from tempest.api.volume import base
 from tempest.common import waiters
 from tempest.lib import decorators
@@ -56,7 +54,7 @@
         # List volume transfers, the result should be greater than
         # or equal to 1
         body = self.client.list_volume_transfers()['transfers']
-        self.assertThat(len(body), matchers.GreaterThan(0))
+        self.assertNotEmpty(body)
 
         # Accept a volume transfer by alt_tenant
         body = self.alt_client.accept_volume_transfer(
diff --git a/tempest/api/volume/test_volumes_actions.py b/tempest/api/volume/test_volumes_actions.py
index 0e7f1e9..8541c6d 100644
--- a/tempest/api/volume/test_volumes_actions.py
+++ b/tempest/api/volume/test_volumes_actions.py
@@ -38,7 +38,7 @@
     @test.services('compute')
     def test_attach_detach_volume_to_instance(self):
         # Create a server
-        server = self.create_server(wait_until='ACTIVE')
+        server = self.create_server()
         # Volume is attached and detached successfully from an instance
         self.volumes_client.attach_volume(self.volume['id'],
                                           instance_uuid=server['id'],
@@ -69,7 +69,7 @@
     @test.services('compute')
     def test_get_volume_attachment(self):
         # Create a server
-        server = self.create_server(wait_until='ACTIVE')
+        server = self.create_server()
         # Verify that a volume's attachment information is retrieved
         self.volumes_client.attach_volume(self.volume['id'],
                                           instance_uuid=server['id'],
diff --git a/tempest/api/volume/test_volumes_backup.py b/tempest/api/volume/test_volumes_backup.py
index 5ad209c..da4324a 100644
--- a/tempest/api/volume/test_volumes_backup.py
+++ b/tempest/api/volume/test_volumes_backup.py
@@ -108,7 +108,7 @@
         volume = self.create_volume()
         self.addCleanup(self.volumes_client.delete_volume,
                         volume['id'])
-        server = self.create_server(wait_until='ACTIVE')
+        server = self.create_server()
         # Attach volume to instance
         self.attach_volume(server['id'], volume['id'])
         # Create backup using force flag
diff --git a/tempest/api/volume/test_volumes_negative.py b/tempest/api/volume/test_volumes_negative.py
index 9180088..4e19e62 100644
--- a/tempest/api/volume/test_volumes_negative.py
+++ b/tempest/api/volume/test_volumes_negative.py
@@ -170,7 +170,7 @@
     @decorators.idempotent_id('f5e56b0a-5d02-43c1-a2a7-c9b792c2e3f6')
     @test.services('compute')
     def test_attach_volumes_with_nonexistent_volume_id(self):
-        server = self.create_server(wait_until='ACTIVE')
+        server = self.create_server()
 
         self.assertRaises(lib_exc.NotFound,
                           self.volumes_client.attach_volume,
diff --git a/tempest/api/volume/test_volumes_snapshots.py b/tempest/api/volume/test_volumes_snapshots.py
index 99918eb..44c1def 100644
--- a/tempest/api/volume/test_volumes_snapshots.py
+++ b/tempest/api/volume/test_volumes_snapshots.py
@@ -39,7 +39,7 @@
     @test.services('compute')
     def test_snapshot_create_delete_with_volume_in_use(self):
         # Create a test instance
-        server = self.create_server(wait_until='ACTIVE')
+        server = self.create_server()
         self.attach_volume(server['id'], self.volume_origin['id'])
 
         # Snapshot a volume which attached to an instance with force=False
@@ -65,7 +65,7 @@
         snapshot1 = self.create_snapshot(self.volume_origin['id'])
 
         # Create a server and attach it
-        server = self.create_server(wait_until='ACTIVE')
+        server = self.create_server()
         self.attach_volume(server['id'], self.volume_origin['id'])
 
         # Now that the volume is attached, create another snapshots
diff --git a/tempest/common/utils/linux/remote_client.py b/tempest/common/utils/linux/remote_client.py
index 5ab980b..99a628e 100644
--- a/tempest/common/utils/linux/remote_client.py
+++ b/tempest/common/utils/linux/remote_client.py
@@ -93,12 +93,12 @@
     def get_nic_name_by_mac(self, address):
         cmd = "ip -o link | awk '/%s/ {print $2}'" % address
         nic = self.exec_command(cmd)
-        return nic.strip().strip(":").lower()
+        return nic.strip().strip(":").split('@')[0].lower()
 
     def get_nic_name_by_ip(self, address):
         cmd = "ip -o addr | awk '/%s/ {print $2}'" % address
         nic = self.exec_command(cmd)
-        return nic.strip().strip(":").lower()
+        return nic.strip().strip(":").split('@')[0].lower()
 
     def get_dns_servers(self):
         cmd = 'cat /etc/resolv.conf'
diff --git a/tempest/lib/common/rest_client.py b/tempest/lib/common/rest_client.py
index d72b4dd..63cf07f 100644
--- a/tempest/lib/common/rest_client.py
+++ b/tempest/lib/common/rest_client.py
@@ -474,7 +474,7 @@
             # Ensure there are not more than one top-level keys
             # NOTE(freerunner): Ensure, that JSON is not nullable to
             # to prevent StopIteration Exception
-            if len(body.keys()) != 1:
+            if not hasattr(body, "keys") or len(body.keys()) != 1:
                 return body
             # Just return the "wrapped" element
             first_key, first_item = six.next(six.iteritems(body))
diff --git a/tempest/scenario/manager.py b/tempest/scenario/manager.py
index b692acf..f25ab1d 100644
--- a/tempest/scenario/manager.py
+++ b/tempest/scenario/manager.py
@@ -822,7 +822,7 @@
     def _get_network_by_name(self, network_name):
         net = self.os_admin.networks_client.list_networks(
             name=network_name)['networks']
-        self.assertNotEqual(len(net), 0,
+        self.assertNotEmpty(net,
                             "Unable to get network by name: %s" % network_name)
         return net[0]
 
diff --git a/tempest/scenario/test_aggregates_basic_ops.py b/tempest/scenario/test_aggregates_basic_ops.py
index c06d239..25227be 100644
--- a/tempest/scenario/test_aggregates_basic_ops.py
+++ b/tempest/scenario/test_aggregates_basic_ops.py
@@ -52,7 +52,7 @@
 
     def _get_host_name(self):
         hosts = self.hosts_client.list_hosts()['hosts']
-        self.assertGreaterEqual(len(hosts), 1)
+        self.assertNotEmpty(hosts)
         computes = [x for x in hosts if x['service'] == 'compute']
         return computes[0]['host_name']
 
diff --git a/tempest/scenario/test_network_basic_ops.py b/tempest/scenario/test_network_basic_ops.py
index 9aeedad..4efeffd 100644
--- a/tempest/scenario/test_network_basic_ops.py
+++ b/tempest/scenario/test_network_basic_ops.py
@@ -295,7 +295,7 @@
         ssh_client.exec_command("sudo ip link set %s up" % new_nic)
 
     def _get_server_nics(self, ssh_client):
-        reg = re.compile(r'(?P<num>\d+): (?P<nic_name>\w+):')
+        reg = re.compile(r'(?P<num>\d+): (?P<nic_name>\w+)[@]?.*:')
         ipatxt = ssh_client.exec_command("ip address")
         return reg.findall(ipatxt)
 
diff --git a/tempest/tests/lib/test_rest_client.py b/tempest/tests/lib/common/test_rest_client.py
similarity index 99%
rename from tempest/tests/lib/test_rest_client.py
rename to tempest/tests/lib/common/test_rest_client.py
index ace2b80..4c0bb57 100644
--- a/tempest/tests/lib/test_rest_client.py
+++ b/tempest/tests/lib/common/test_rest_client.py
@@ -276,6 +276,11 @@
         body = self.rest_client._parse_resp(json.dumps(self.null_dict))
         self.assertEqual(self.null_dict, body)
 
+    def test_parse_empty_list(self):
+        empty_list = []
+        body = self.rest_client._parse_resp(json.dumps(empty_list))
+        self.assertEqual(empty_list, body)
+
 
 class TestRestClientErrorCheckerJSON(base.TestCase):
     c_type = "application/json"
diff --git a/tools/check_logs.py b/tools/check_logs.py
index f82b387..fc21f75 100755
--- a/tools/check_logs.py
+++ b/tools/check_logs.py
@@ -25,7 +25,6 @@
 import six.moves.urllib.request as urlreq
 import yaml
 
-
 # DEVSTACK_GATE_GRENADE is either unset if grenade is not running
 # or a string describing what type of grenade run to perform.
 is_grenade = os.environ.get('DEVSTACK_GATE_GRENADE') is not None
@@ -137,7 +136,7 @@
     with open(WHITELIST_FILE) as stream:
         loaded = yaml.safe_load(stream)
         if loaded:
-            for (name, l) in loaded.iteritems():
+            for (name, l) in six.iteritems(loaded):
                 for w in l:
                     assert 'module' in w, 'no module in %s' % name
                     assert 'message' in w, 'no message in %s' % name
diff --git a/tools/find_stack_traces.py b/tools/find_stack_traces.py
index 2ba8b16..1f2b88b 100755
--- a/tools/find_stack_traces.py
+++ b/tools/find_stack_traces.py
@@ -126,8 +126,8 @@
 
 
 def print_stats(items, fname, verbose=False):
-    errors = len(filter(lambda x: x.level == "ERROR", items))
-    traces = len(filter(lambda x: x.level == "TRACE", items))
+    errors = len([x for x in items if x.level == "ERROR"])
+    traces = len([x for x in items if x.level == "TRACE"])
     print("%d ERRORS found in %s" % (errors, fname))
     print("%d TRACES found in %s" % (traces, fname))
 
diff --git a/tools/generate-tempest-plugins-list.py b/tools/generate-tempest-plugins-list.py
index f94da86..238a976 100644
--- a/tools/generate-tempest-plugins-list.py
+++ b/tools/generate-tempest-plugins-list.py
@@ -72,7 +72,7 @@
 # json library won't choke.
 projects = sorted(filter(is_in_openstack_namespace, json.loads(r.read()[4:])))
 
-found_plugins = filter(has_tempest_plugin, projects)
+found_plugins = list(filter(has_tempest_plugin, projects))
 
 # Every element of the found_plugins list begins with "openstack/".
 # We drop those initial 10 octets when printing the list.