doc: update :attr: to :py:attr: for modern Sphinx.

diff --git a/libbe/util/utility.py b/libbe/util/utility.py
index 99d28e58ef8de14c484d80c6d471cbef98b13b34..08ffca819d4f615bb737c1c25bf674e169b9a768 100644 (file)
--- a/libbe/util/utility.py
+++ b/libbe/util/utility.py
@@ -199,7 +199,7 @@ def iterable_full_of_strings(value, alternative=None):
     """Require an iterable full of strings.
 
     This is useful, for example, in validating `*.extra_strings`.
-    See :attr:`libbe.bugdir.BugDir.extra_strings`
+    See :py:attr:`libbe.bugdir.BugDir.extra_strings`
 
     Parameters
     ----------