diff --git a/tests/test_account_invoice.py b/tests/test_account_invoice.py
index 05c5b5716e..cbaca8505d 100644
--- a/tests/test_account_invoice.py
+++ b/tests/test_account_invoice.py
@@ -1,14 +1,5 @@
-#!/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.
-
-import sys
-import os
-DIR = os.path.abspath(os.path.normpath(os.path.join(__file__,
-    '..', '..', '..', '..', '..', 'trytond')))
-if os.path.isdir(DIR):
-    sys.path.insert(0, os.path.dirname(DIR))
-
 import unittest
 import doctest
 import datetime
@@ -20,9 +11,7 @@ from trytond.transaction import Transaction
 
 
 class AccountInvoiceTestCase(unittest.TestCase):
-    '''
-    Test AccountInvoice module.
-    '''
+    'Test AccountInvoice module'
 
     def setUp(self):
         trytond.tests.test_tryton.install_module('account_invoice')
@@ -30,21 +19,15 @@ class AccountInvoiceTestCase(unittest.TestCase):
         self.currency = POOL.get('currency.currency')
 
     def test0005views(self):
-        '''
-        Test views.
-        '''
+        'Test views'
         test_view('account_invoice')
 
     def test0006depends(self):
-        '''
-        Test depends.
-        '''
+        'Test depends'
         test_depends()
 
     def test0010payment_term(self):
-        '''
-        Test payment_term.
-        '''
+        'Test payment_term'
         with Transaction().start(DB_NAME, USER, context=CONTEXT):
             cu1, = self.currency.create([{
                         'name': 'cu1',
@@ -103,6 +86,3 @@ def suite():
             setUp=doctest_dropdb, tearDown=doctest_dropdb, encoding='utf-8',
             optionflags=doctest.REPORT_ONLY_FIRST_FAILURE))
     return suite
-
-if __name__ == '__main__':
-    unittest.TextTestRunner(verbosity=2).run(suite())