bpo-38870: Expose a function to unparse an ast object in the ast module (GH-17302)

Add ast.unparse() as a function in the ast module that can be used to unparse an
ast.AST object and produce a string with code that would produce an equivalent ast.AST
object when parsed.

1 files changed, 13 insertions, 0 deletions

diff --git a/Doc/library/ast.rst b/Doc/library/ast.rst
index b468f4235d..a7e0729b90 100644
--- a/Doc/library/ast.rst
+++ b/Doc/library/ast.rst
@@ -161,6 +161,19 @@ and classes for traversing abstract syntax trees:
       Added ``type_comments``, ``mode='func_type'`` and ``feature_version``.
 
 
+.. function:: unparse(ast_obj)
+
+   Unparse an :class:`ast.AST` object and generate a string with code
+   that would produce an equivalent :class:`ast.AST` object if parsed
+   back with :func:`ast.parse`.
+
+   .. warning::
+      The produced code string will not necesarily be equal to the original
+      code that generated the :class:`ast.AST` object.
+
+   .. versionadded:: 3.9
+
+
 .. function:: literal_eval(node_or_string)
 
    Safely evaluate an expression node or a string containing a Python literal or