[3.7] bpo-33475: Fix and improve converting annotations to strings. (GH-6774). (GH-6927)

(cherry picked from commit 64fddc423fcbe90b8088446c63385ec0aaf3077c)

Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>
diff --git a/Include/ast.h b/Include/ast.h
index 639c4f8..5bc2b05 100644
--- a/Include/ast.h
+++ b/Include/ast.h
@@ -19,9 +19,7 @@
 #ifndef Py_LIMITED_API
 
 /* _PyAST_ExprAsUnicode is defined in ast_unparse.c */
-PyAPI_FUNC(PyObject *) _PyAST_ExprAsUnicode(
-    expr_ty e,
-    int omit_parens);
+PyAPI_FUNC(PyObject *) _PyAST_ExprAsUnicode(expr_ty);
 
 #endif /* !Py_LIMITED_API */