Perform build and magnum tuning

Building o//third_party/python now takes 5 seconds on my PC

This change works towards modifying Python to use runtime dispatching
when appropriate. For example, when loading the magnums in the socket
module, it's a good idea to check if the magnum is zero, because that
means the local system platform doesn't support it.

third_party/python/PC/config.c

@@ -1,9 +1,10 @@
+/* clang-format off */
 /* Module configuration */
 
 /* This file contains the table of built-in modules.
     See create_builtin() in import.c. */
 
-#include "Python.h"
+#include "third_party/python/Include/Python.h"
 
 extern PyObject* PyInit_array(void);
 #ifndef MS_WINI64