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/Programs/python.c

@@ -1,20 +1,9 @@
 /* Minimal main program -- everything is loaded from the library */
+/* clang-format off */
 
-#include "Python.h"
+#include "third_party/python/Include/Python.h"
 #include "libc/unicode/locale.h"
 
-#ifdef __FreeBSD__
-#include <fenv.h>
-#endif
-
-#ifdef MS_WINDOWS
-int
-wmain(int argc, wchar_t **argv)
-{
-    return Py_Main(argc, argv);
-}
-#else
-
 int
 main(int argc, char **argv)
 {
@@ -79,4 +68,3 @@ main(int argc, char **argv)
     PyMem_RawFree(argv_copy2);
     return res;
 }
-#endif