diff --git a/tests/test_connection.py b/tests/test_connection.py
index e62e51e3..dc3cfb00 100755
--- a/tests/test_connection.py
+++ b/tests/test_connection.py
@@ -204,13 +204,13 @@ class IsolationLevelsTestCase(unittest.TestCase):
         conn = self.connect()
         curs = conn.cursor()
 
-        levels = (
+        levels = [
             (None, psycopg2.extensions.ISOLATION_LEVEL_AUTOCOMMIT),
             ('read uncommitted', psycopg2.extensions.ISOLATION_LEVEL_READ_UNCOMMITTED),
             ('read committed', psycopg2.extensions.ISOLATION_LEVEL_READ_COMMITTED),
             ('repeatable read', psycopg2.extensions.ISOLATION_LEVEL_REPEATABLE_READ),
             ('serializable', psycopg2.extensions.ISOLATION_LEVEL_SERIALIZABLE),
-        )
+        ]
         for name, level in levels:
             conn.set_isolation_level(level)