diff --git a/src/allmydata/test/mutable/test_exceptions.py b/src/allmydata/test/mutable/test_exceptions.py
index ed6cab1b0..6a9b2b575 100644
--- a/src/allmydata/test/mutable/test_exceptions.py
+++ b/src/allmydata/test/mutable/test_exceptions.py
@@ -1,3 +1,16 @@
+"""
+Ported to Python 3.
+"""
+
+from __future__ import absolute_import
+from __future__ import division
+from __future__ import print_function
+from __future__ import unicode_literals
+
+from future.utils import PY2
+if PY2:
+    from future.builtins import filter, map, zip, ascii, chr, hex, input, next, oct, open, pow, round, super, bytes, dict, list, object, range, str, max, min  # noqa: F401
+
 from twisted.trial import unittest
 from allmydata.mutable.common import NeedMoreDataError, UncoordinatedWriteError
 
diff --git a/src/allmydata/util/_python3.py b/src/allmydata/util/_python3.py
index a7f74a686..a6ee10169 100644
--- a/src/allmydata/util/_python3.py
+++ b/src/allmydata/util/_python3.py
@@ -95,6 +95,7 @@ PORTED_MODULES = [
 PORTED_TEST_MODULES = [
     "allmydata.test.mutable.test_datahandle",
     "allmydata.test.mutable.test_different_encoding",
+    "allmydata.test.mutable.test_exceptions",
     "allmydata.test.mutable.test_filehandle",
     "allmydata.test.mutable.test_filenode",
     "allmydata.test.test_abbreviate",