Part of previous commit.

src/zope/session/_compat.py

@@ -0,0 +1,32 @@
+##############################################################################
+#
+# Copyright (c) 2015 Zope Foundation and Contributors.
+# All Rights Reserved.
+#
+# This software is subject to the provisions of the Zope Public License,
+# Version 2.1 (ZPL).  A copy of the ZPL should accompany this distribution.
+# THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED
+# WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+# WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS
+# FOR A PARTICULAR PURPOSE
+#
+##############################################################################
+import sys
+
+if sys.version_info[0] < 3:
+
+    PY2 = True
+    PY3 = False
+
+    def _u(s, encoding='unicode_escape'):
+        return unicode(s, encoding)
+
+else:
+
+    PY2 = False
+    PY3 = True
+
+    def _u(s, encoding=None):
+        if encoding is None:
+            return s
+        return str(s, encoding)