Remove the PyAST_Validate() function. It is no longer possible to build a AST object (mod_ty type) with the public C API. The function was already excluded from the limited C API (PEP 384). Rename PyAST_Validate() function to _PyAST_Validate(), move it to the internal C API, and don't export it anymore (replace PyAPI_FUNC with extern). The function was added in bpo-12575 by the commit 832bfe2ebd5ecfa92031cd40c8b41835ba90487f.
Miscellaneous source files for the main Python shared library