diff --git a/tests/book.py b/tests/book.py
index b6421e4..8678173 100644
--- a/tests/book.py
+++ b/tests/book.py
@@ -3,7 +3,7 @@
 # The COPYRIGHT file at the top level of this repository contains the
 # full copyright notices and license terms.
 
-from trytond.tests.test_tryton import ModuleTestCase, with_transaction
+from trytond.tests.test_tryton import with_transaction
 from trytond.pool import Pool
 from trytond.transaction import Transaction
 from trytond.exceptions import UserError
@@ -11,10 +11,9 @@ from datetime import date
 from decimal import Decimal
 
 
-class BookTestCase(ModuleTestCase):
-    'Test cashbook book module'
-    module = 'cashbook'
-
+class BookTestCase(object):
+    """ test cashbook
+    """
     def prep_sequence(self, name='Book Sequ'):
         """ create numbering-equence
         """
diff --git a/tests/bookingwiz.py b/tests/bookingwiz.py
index 2bb6f7d..690fcd6 100644
--- a/tests/bookingwiz.py
+++ b/tests/bookingwiz.py
@@ -3,7 +3,7 @@
 # The COPYRIGHT file at the top level of this repository contains the
 # full copyright notices and license terms.
 
-from trytond.tests.test_tryton import ModuleTestCase, with_transaction
+from trytond.tests.test_tryton import with_transaction
 from trytond.pool import Pool
 from trytond.transaction import Transaction
 from datetime import date
@@ -11,10 +11,9 @@ from decimal import Decimal
 from unittest.mock import MagicMock
 
 
-class BookingWizardTestCase(ModuleTestCase):
-    'Test cashbook booking wizard module'
-    module = 'cashbook'
-
+class BookingWizardTestCase(object):
+    """ test booking wizard
+    """
     @with_transaction()
     def test_bookwiz_expense(self):
         """ run booking-wizard to store expense
diff --git a/tests/category.py b/tests/category.py
index e08dde9..78ce5c3 100644
--- a/tests/category.py
+++ b/tests/category.py
@@ -3,16 +3,15 @@
 # The COPYRIGHT file at the top level of this repository contains the
 # full copyright notices and license terms.
 
-from trytond.tests.test_tryton import ModuleTestCase, with_transaction
+from trytond.tests.test_tryton import with_transaction
 from trytond.pool import Pool
 from trytond.transaction import Transaction
 from trytond.exceptions import UserError
 
 
-class CategoryTestCase(ModuleTestCase):
-    'Test cashbook categoy module'
-    module = 'cashbook'
-
+class CategoryTestCase(object):
+    """ test category
+    """
     def prep_category(self, name='Cat1', cattype='out'):
         """ create category
         """
diff --git a/tests/config.py b/tests/config.py
index 542d1bf..a1eb701 100644
--- a/tests/config.py
+++ b/tests/config.py
@@ -3,7 +3,7 @@
 # The COPYRIGHT file at the top level of this repository contains the
 # full copyright notices and license terms.
 
-from trytond.tests.test_tryton import ModuleTestCase, with_transaction
+from trytond.tests.test_tryton import with_transaction
 from trytond.pool import Pool
 from trytond.transaction import Transaction
 from trytond.modules.company.tests import create_company
@@ -11,10 +11,9 @@ from datetime import date
 from decimal import Decimal
 
 
-class ConfigTestCase(ModuleTestCase):
-    'Test config type module'
-    module = 'cashbook'
-
+class ConfigTestCase(object):
+    """ test config
+    """
     def prep_company(self):
         """ get/create company
         """
diff --git a/tests/currency.py b/tests/currency.py
index 21ce968..316ddb3 100644
--- a/tests/currency.py
+++ b/tests/currency.py
@@ -3,7 +3,7 @@
 # The COPYRIGHT file at the top level of this repository contains the
 # full copyright notices and license terms.
 
-from trytond.tests.test_tryton import ModuleTestCase, with_transaction
+from trytond.tests.test_tryton import with_transaction
 from trytond.pool import Pool
 from trytond.modules.cashbook.model import CACHEKEY_CURRENCY, ENABLE_CACHE
 from datetime import date
@@ -11,10 +11,9 @@ from decimal import Decimal
 import time
 
 
-class CurrencyTestCase(ModuleTestCase):
-    'Test cache for currency'
-    module = 'cashbook'
-
+class CurrencyTestCase(object):
+    """ test currency
+    """
     @with_transaction()
     def test_currency_update_cache(self):
         """ add/update/del rate of currency, check cache
diff --git a/tests/reconciliation.py b/tests/reconciliation.py
index 42bb0a3..ebdb4b1 100644
--- a/tests/reconciliation.py
+++ b/tests/reconciliation.py
@@ -3,17 +3,16 @@
 # The COPYRIGHT file at the top level of this repository contains the
 # full copyright notices and license terms.
 
-from trytond.tests.test_tryton import ModuleTestCase, with_transaction
+from trytond.tests.test_tryton import with_transaction
 from trytond.pool import Pool
 from trytond.exceptions import UserError
 from datetime import date
 from decimal import Decimal
 
 
-class ReconTestCase(ModuleTestCase):
-    'Test cashbook reconciliation module'
-    module = 'cashbook'
-
+class ReconTestCase(object):
+    """ test reconciliation
+    """
     @with_transaction()
     def test_recon_check_overlap_start(self):
         """ create, check deny of overlap date - date_from
diff --git a/tests/splitline.py b/tests/splitline.py
index 3cacc35..629b7e9 100644
--- a/tests/splitline.py
+++ b/tests/splitline.py
@@ -3,15 +3,15 @@
 # The COPYRIGHT file at the top level of this repository contains the
 # full copyright notices and license terms.
 
-from trytond.tests.test_tryton import ModuleTestCase, with_transaction
+from trytond.tests.test_tryton import with_transaction
 from trytond.pool import Pool
 from datetime import date
 from decimal import Decimal
 
 
-class SplitLineTestCase(ModuleTestCase):
-    'Test split line module'
-    module = 'cashbook'
+class SplitLineTestCase(object):
+    """ test split lines
+    """
 
     @with_transaction()
     def test_splitline_in_category(self):