Add an attribution to the Green Tree Snakes in the AST docs (GH-24727)

diff --git a/Doc/library/ast.rst b/Doc/library/ast.rst
index aaedfbe1b9c013440e676543053f8d620a46ae11..b5e1be826911575b2a89c7c0b48a62714d340ea7 100644 (file)
--- a/Doc/library/ast.rst
+++ b/Doc/library/ast.rst
@@ -140,6 +140,11 @@ Node classes
    In the meantime, instantiating them will return an instance of
    a different class.
 
+.. note::
+    The descriptions of the specific node classes displayed here
+    were initially adapted from the fantastic `Green Tree
+    Snakes <https://greentreesnakes.readthedocs.io/en/latest/>`__ project and
+    all its contributors.
 
 Literals
 ^^^^^^^^