diff --git a/src/rss.py b/src/rss.py
index ab19681..c10aa32 100644
--- a/src/rss.py
+++ b/src/rss.py
@@ -6,7 +6,7 @@ try:
     import feedgenerator
 except ImportError:
     traceback.print_exc()
-    def write_feed(posts, filename, params):
+    def write_feed(posts, filename, params, tagname=None):
         pass
     print("\trss disabled - missing dependency", file=sys.stderr)
     print("\tYour microblog still may have been generated.", file=sys.stderr)
@@ -65,9 +65,9 @@ def enrich_msg(lines, is_atom=True):
             content.append(line)
     return content
 
-def write_feed(posts, filename, params, tagname=str()):
+def write_feed(posts, filename, params, tagname=None):
     feed = None
-    if tagname != str():
+    if tagname:
         t = params["title_tagged"].format(
             __tagname__ = tagname,
             __title__ = params["title"])