Add ToTagSetConvertible to docs

Author: inducer

pytools/tag.py

@@ -21,6 +21,12 @@
 .. class:: TagT
 
     A type variable with lower bound :class:`Tag`.
+
+.. autodata:: ToTagSetConvertible
+    :no-index:
+.. class:: ToTagSetConvertible
+
+    See above.
 """
 
 from __future__ import annotations