diff --git a/__init__.py b/__init__.py
index 91f5675299..7f277d2ea6 100644
--- a/__init__.py
+++ b/__init__.py
@@ -1,5 +1,5 @@
-#This file is part of Tryton.  The COPYRIGHT file at the top level of this
-#repository contains the full copyright notices and license terms.
+# This file is part of Tryton.  The COPYRIGHT file at the top level of
+# this repository contains the full copyright notices and license terms.
 
 from trytond.pool import Pool
 from .party import *
diff --git a/sale.py b/sale.py
index bdb963fde6..5648135958 100644
--- a/sale.py
+++ b/sale.py
@@ -1,8 +1,7 @@
-#This file is part of Tryton.  The COPYRIGHT file at the top level of this
-#repository contains the full copyright notices and license terms.
+# This file is part of Tryton.  The COPYRIGHT file at the top level of
+# this repository contains the full copyright notices and license terms.
 
 from trytond.pool import PoolMeta
-from trytond.transaction import Transaction
 
 __metaclass__ = PoolMeta
 __all__ = ['Sale']
diff --git a/setup.py b/setup.py
index 588276fedd..21843ba547 100644
--- a/setup.py
+++ b/setup.py
@@ -1,6 +1,6 @@
 #!/usr/bin/env python
-#This file is part of Tryton.  The COPYRIGHT file at the top level of
-#this repository contains the full copyright notices and license terms.
+# This file is part of Tryton.  The COPYRIGHT file at the top level of
+# this repository contains the full copyright notices and license terms.
 
 from setuptools import setup
 import re
diff --git a/tests/__init__.py b/tests/__init__.py
index 89c197649a..0851475767 100644
--- a/tests/__init__.py
+++ b/tests/__init__.py
@@ -1,5 +1,5 @@
-#This file is part of Tryton.  The COPYRIGHT file at the top level of this
-#repository contains the full copyright notices and license terms.
+# This file is part of Tryton.  The COPYRIGHT file at the top level of
+# this repository contains the full copyright notices and license terms.
 
 from .test_sale_shipment_grouping import suite
 
diff --git a/tests/test_sale_shipment_grouping.py b/tests/test_sale_shipment_grouping.py
index df4b4da94e..7459379862 100644
--- a/tests/test_sale_shipment_grouping.py
+++ b/tests/test_sale_shipment_grouping.py
@@ -1,5 +1,5 @@
-#This file is part of Tryton.  The COPYRIGHT file at the top level of this
-#repository contains the full copyright notices and license terms.
+# This file is part of Tryton.  The COPYRIGHT file at the top level of
+# this repository contains the full copyright notices and license terms.
 import unittest
 import doctest
 import trytond.tests.test_tryton