typo

generators.html

@@ -297,7 +297,7 @@ rules = []
 
 <p class=d>[<a href=examples/plural5.py>download <code>plural5.py</code></a>]
 <pre class='nd pp'><code>def rules(rules_filename):
-    with open('plural5-rules.txt', encoding='utf-8') as pattern_file:
+    with open(rules_filename, encoding='utf-8') as pattern_file:
         for line in pattern_file:
             pattern, search, replace = line.split(None, 3)
             yield build_match_and_apply_functions(pattern, search, replace)