implementing iterators in pyd

I am trying to provide python iterator support to a D class wrapped with pyd.wrap_class. According to the documentation (https://github.com/ariovistus/pyd/wiki/ClassWrap#Iterator_wrapping and http://pyd.readthedocs.org/en/latest/classes.html#iterator-wrapping) the next method should return null to signal termination.

Here is my minimal D example:

import pyd.pyd;
import pyd.pydobject;
import pyd.class_wrap;

class IteratorTest
{
    IteratorTest _iter()
    {
        return this;
    }

    PydObject _next()
    {
        return null;
    }

}

extern(C) void PydMain() {
    module_init();

    wrap_class!(
        IteratorTest,
        Def!(IteratorTest._iter, PyName!("__iter__")),
        Def!(IteratorTest._next, PyName!("next"))
    );
}

However, invoking this with the python test code

for item in IteratorTest() :
    print item

prints me a never ending stream of None. Does anyone know what I am doing wrong here?

Thanks to DejanLekic I found the solution to the problem. The correct implementation is (note the changed signature of the _next() method):

import pyd.pyd;
import pyd.class_wrap;
import deimos.python.object;

class IteratorTest
{
    IteratorTest _iter()
    {
        return this;
    }

    PyObject *_next()
    {
        return null;
    }

}

extern(C) void PydMain() {
    module_init();

    wrap_class!(
        IteratorTest,
        Def!(IteratorTest._iter, PyName!("__iter__")),
        Def!(IteratorTest._next, PyName!("next"))
    );
}