copy(): Make sure the copy of a derived class cannot share the data of the original by replacing self.data temporarily, then using the update() method on the new mapping object to populate it. This closes SF bug #476616.

/* Minimal main program -- everything is loaded from the library */

#include "Python.h"

extern DL_EXPORT(int) Py_Main(int, char **);

int
main(int argc, char **argv)
{
	return Py_Main(argc, argv);
}