in with the new. i have the bits in places where i think they should be, now i just need to work on the import scheme layout

flask/session.py

@@ -0,0 +1,28 @@
+class Session(SecureCookie):
+    """Expands the session with support for switching between permanent
+    and non-permanent sessions.
+    """
+
+    def _get_permanent(self):
+        return self.get('_permanent', False)
+
+    def _set_permanent(self, value):
+        self['_permanent'] = bool(value)
+
+    permanent = property(_get_permanent, _set_permanent)
+    del _get_permanent, _set_permanent
+
+
+class _NullSession(Session):
+    """Class used to generate nicer error messages if sessions are not
+    available.  Will still allow read-only access to the empty session
+    but fail on setting.
+    """
+
+    def _fail(self, *args, **kwargs):
+        raise RuntimeError('the session is unavailable because no secret '
+                           'key was set.  Set the secret_key on the '
+                           'application to something unique and secret')
+    __setitem__ = __delitem__ = clear = pop = popitem = \
+        update = setdefault = _fail
+    del _fail