gh-108113: Make it possible to create an optimized AST (#108154)

Lib/ast.py

@@ -32,13 +32,15 @@ from enum import IntEnum, auto, _simple_enum
 
 
 def parse(source, filename='<unknown>', mode='exec', *,
-          type_comments=False, feature_version=None):
+          type_comments=False, feature_version=None, optimize=-1):
     """
     Parse the source into an AST node.
     Equivalent to compile(source, filename, mode, PyCF_ONLY_AST).
     Pass type_comments=True to get back type comments where the syntax allows.
     """
     flags = PyCF_ONLY_AST
+    if optimize > 0:
+        flags |= PyCF_OPTIMIZED_AST
     if type_comments:
         flags |= PyCF_TYPE_COMMENTS
     if feature_version is None:
@@ -50,7 +52,7 @@ def parse(source, filename='<unknown>', mode='exec', *,
         feature_version = minor
     # Else it should be an int giving the minor version for 3.x.
     return compile(source, filename, mode, flags,
-                   _feature_version=feature_version)
+                   _feature_version=feature_version, optimize=optimize)
 
 
 def literal_eval(node_or_string):