Docs: Added ast_utils

docs/classes.rst

@@ -73,4 +73,18 @@ InteractiveParser
     :members: choices, feed_token, copy, pretty, resume_parse, exhaust_lexer, accepts
 
 .. autoclass:: lark.parsers.lalr_interactive_parser.ImmutableInteractiveParser
-    :members: choices, feed_token, copy, pretty, resume_parse, exhaust_lexer, accepts
+    :members: choices, feed_token, copy, pretty, resume_parse, exhaust_lexer, accepts
+
+
+ast_utils
+---------
+
+For an example of using ``ast_utils``, see `/examples/advanced/create_ast.py`_ 
+
+.. autoclass:: lark.ast_utils.Ast
+
+.. autoclass:: lark.ast_utils.AsList
+
+.. autofunction:: lark.ast_utils.create_transformer
+
+.. _/examples/advanced/create_ast.py: examples/advanced/create_ast.html