diff --git a/langchain/chains/query_constructor/parser.py b/langchain/chains/query_constructor/parser.py
index 22cfc90a56..a0c7f229d9 100644
--- a/langchain/chains/query_constructor/parser.py
+++ b/langchain/chains/query_constructor/parser.py
@@ -10,7 +10,12 @@ try:
         )
     from lark import Lark, Transformer, v_args
 except ImportError:
-    pass
+
+    def v_args(*args: Any, **kwargs: Any) -> Any:  # type: ignore
+        return lambda _: None
+
+    Transformer = object  # type: ignore
+    Lark = object  # type: ignore
 
 from langchain.chains.query_constructor.ir import (
     Comparator,