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/__init__.py b/__init__.py
index 32bc3ef5b3..1347d596d2 100644
--- a/__init__.py
+++ b/__init__.py
@@ -2,11 +2,11 @@
 # this repository contains the full copyright notices and license terms.
 
 from trytond.pool import Pool
-from .invoice import *
+from . import invoice
 
 
 def register():
     Pool.register(
-        Invoice,
-        InvoiceLine,
+        invoice.Invoice,
+        invoice.InvoiceLine,
         module='account_invoice_line_standalone', type_='model')
diff --git a/invoice.py b/invoice.py
index bdaab9eb84..546381d959 100644
--- a/invoice.py
+++ b/invoice.py
@@ -4,8 +4,6 @@ from trytond.pyson import Eval
 from trytond.transaction import Transaction
 from trytond.pool import PoolMeta
 
-__all__ = ['Invoice', 'InvoiceLine']
-
 
 class Invoice(metaclass=PoolMeta):
     __name__ = 'account.invoice'
diff --git a/setup.py b/setup.py
index 60c166acdc..1a50f8c248 100755
--- a/setup.py
+++ b/setup.py
@@ -79,8 +79,8 @@ setup(name=name,
     keywords='tryton account standalone invoice line',
     package_dir={'trytond.modules.account_invoice_line_standalone': '.'},
     packages=(
-        ['trytond.modules.account_invoice_line_standalone'] +
-        ['trytond.modules.account_invoice_line_standalone.%s' % p
+        ['trytond.modules.account_invoice_line_standalone']
+        + ['trytond.modules.account_invoice_line_standalone.%s' % p
             for p in find_packages()]
         ),
     package_data={
@@ -94,7 +94,8 @@ setup(name=name,
         'Intended Audience :: Developers',
         'Intended Audience :: Legal Industry',
         'Intended Audience :: Manufacturing',
-        '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 :: Chinese (Simplified)',
diff --git a/tests/__init__.py b/tests/__init__.py
index 44d3ca6cb8..acda3a2c6a 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_invoice_line_standalone.tests.test_account_invoice_line_standalone import suite
+    from trytond.modules.account_invoice_line_standalone.tests.test_account_invoice_line_standalone import suite  # noqa: E501
 except ImportError:
     from .test_account_invoice_line_standalone import suite