diff --git a/tests/test_sale_shipment_cost.py b/tests/test_sale_shipment_cost.py
index 5e0b43aee6..592e929378 100644
--- a/tests/test_sale_shipment_cost.py
+++ b/tests/test_sale_shipment_cost.py
@@ -11,8 +11,7 @@ if os.path.isdir(DIR):
 import unittest
 import doctest
 import trytond.tests.test_tryton
-from trytond.tests.test_tryton import test_view, test_depends
-from trytond.backend.sqlite.database import Database as SQLiteDatabase
+from trytond.tests.test_tryton import test_view, test_depends, doctest_dropdb
 
 
 class SaleShipmentCostTestCase(unittest.TestCase):
@@ -36,19 +35,6 @@ class SaleShipmentCostTestCase(unittest.TestCase):
         test_depends()
 
 
-def doctest_dropdb(test):
-    '''
-    Remove sqlite memory database
-    '''
-    database = SQLiteDatabase().connect()
-    cursor = database.cursor(autocommit=True)
-    try:
-        database.drop(cursor, ':memory:')
-        cursor.commit()
-    finally:
-        cursor.close()
-
-
 def suite():
     suite = trytond.tests.test_tryton.suite()
     suite.addTests(unittest.TestLoader().loadTestsFromTestCase(