Change %c format specifier for PyArg_ParseTuple() so that it accepts a unicode character (an int * must be passed as the argument). Change %c format specifier for Py_BuildValue() so that it outputs a unicode object. Fix datetime.datetime.isoformat(), so that it works if sep is a unicode character > U+00FF.

#include "Python.h"

#ifndef PLATFORM
#define PLATFORM "unknown"
#endif

const char *
Py_GetPlatform(void)
{
	return PLATFORM;
}