fix: join batch, removed code revision, redirects for other pages if batch missing

community/www/batch/discuss.py

@@ -4,3 +4,5 @@ from . import utils
 def get_context(context):
     utils.get_common_context(context)
     context.messages = context.batch.get_messages()
+    if not context.batch:
+        utils.redirect_to_lesson(context.course)