#184: link to Green Tree Snakes. (#260)

Author: ezio-melotti

compiler.rst

@@ -68,6 +68,12 @@ what should be the first ``:`` and require it be an actual ``:`` token.
 Abstract Syntax Trees (AST)
 ---------------------------
 
+
+.. sidebar:: Green Tree Snakes
+
+   See also `Green Tree Snakes - the missing Python AST docs
+   <https://greentreesnakes.readthedocs.io/en/latest/>`_ by Thomas Kluyver.
+
 The abstract syntax tree (AST) is a high-level representation of the
 program structure without the necessity of containing the source code;
 it can be thought of as an abstract representation of the source code.  The

exploring.rst

@@ -55,6 +55,7 @@ building your understanding of both the 2.x and 3.x versions of CPython:
    :widths: 50, 50, 20, 5
 
     "`A guide from parser to objects, observed using GDB`_", "Code walk from Parser, AST, Sym Table and Objects", Louie Lu, 3.7.a0
+    "`Green Tree Snakes`_", "The missing Python AST docs", Thomas Kluyver, 3.6
     "`Yet another guided tour of CPython`_", "A guide for how CPython REPL works", Guido van Rossum, 3.5
     "`Python Asynchronous I/O Walkthrough`_", "How CPython async I/O, generator and coroutine works", Philip Guo, 3.5
 
@@ -70,6 +71,8 @@ building your understanding of both the 2.x and 3.x versions of CPython:
 
 .. _A guide from parser to objects, observed using GDB: https://hackmd.io/s/ByMHBMjFe
 
+.. _Green Tree Snakes: https://greentreesnakes.readthedocs.io/en/latest/
+
 .. _Yet another guided tour of CPython: https://paper.dropbox.com/doc/Yet-another-guided-tour-of-CPython-XY7KgFGn88zMNivGJ4Jzv
 
 .. _Python Asynchronous I/O Walkthrough: http://pgbovine.net/python-async-io-walkthrough.htm