diff --git a/.flake8 b/.flake8
new file mode 100644
index 0000000000..bb03d08a82
--- /dev/null
+++ b/.flake8
@@ -0,0 +1,2 @@
+[flake8]
+ignore=E123,E124,E126,E128,W503
diff --git a/account.py b/account.py
index 36b7ca9d7f..90d8e0e157 100644
--- a/account.py
+++ b/account.py
@@ -2,8 +2,6 @@
 # this repository contains the full copyright notices and license terms.
 from trytond.pool import PoolMeta
 
-__all__ = ['Move']
-
 
 class Move(metaclass=PoolMeta):
     __name__ = 'account.move'
diff --git a/dunning.py b/dunning.py
index f9b1fc1e9b..ed2e16aacc 100644
--- a/dunning.py
+++ b/dunning.py
@@ -7,8 +7,6 @@ from trytond.pool import PoolMeta, Pool
 from trytond.pyson import Eval
 from trytond.transaction import Transaction
 
-__all__ = ['Fee', 'Level', 'Dunning', 'FeeDunningLevel', 'Letter']
-
 
 class Fee(DeactivableMixin, ModelSQL, ModelView):
     'Account Dunning Fee'
diff --git a/setup.py b/setup.py
index f98130027e..75531f5370 100755
--- a/setup.py
+++ b/setup.py
@@ -80,8 +80,9 @@ setup(name=name,
     keywords='account dunning fee',
     package_dir={'trytond.modules.account_dunning_fee': '.'},
     packages=(
-        ['trytond.modules.account_dunning_fee'] +
-        ['trytond.modules.account_dunning_fee.%s' % p for p in find_packages()]
+        ['trytond.modules.account_dunning_fee']
+        + ['trytond.modules.account_dunning_fee.%s' % p
+            for p in find_packages()]
         ),
     package_data={
         'trytond.modules.account_dunning_fee': (info.get('xml', [])
@@ -95,7 +96,8 @@ setup(name=name,
         'Intended Audience :: Developers',
         'Intended Audience :: Financial and Insurance Industry',
         'Intended Audience :: Legal Industry',
-        'License :: OSI Approved :: GNU General Public License v3 or later (GPLv3+)',
+        'License :: OSI Approved :: '
+        'GNU General Public License v3 or later (GPLv3+)',
         'Natural Language :: Bulgarian',
         'Natural Language :: Catalan',
         'Natural Language :: Czech',
diff --git a/tests/__init__.py b/tests/__init__.py
index 27cc5359f3..8b0f92b4c0 100644
--- a/tests/__init__.py
+++ b/tests/__init__.py
@@ -2,7 +2,7 @@
 # this repository contains the full copyright notices and license terms.
 
 try:
-    from trytond.modules.account_dunning_fee.tests.test_account_dunning_fee import suite
+    from trytond.modules.account_dunning_fee.tests.test_account_dunning_fee import suite  # noqa: E501
 except ImportError:
     from .test_account_dunning_fee import suite