#define PY_SSIZE_T_CLEAN
#include <Python.h>

typedef struct {
 PyObject_HEAD
 /* Type-specific fields go here. */
} CustomObject;

static PyTypeObject CustomType = {
 PyVarObject_HEAD_INIT(NULL, 0)
 .tp_name = "custom.Custom",
 .tp_doc = "Custom objects",
 .tp_basicsize = sizeof(CustomObject),
 .tp_itemsize = 0,
 .tp_flags = Py_TPFLAGS_DEFAULT,
 .tp_new = PyType_GenericNew,
};

static PyModuleDef custommodule = {
 PyModuleDef_HEAD_INIT,
 .m_name = "custom",
 .m_doc = "Example module that creates an extension type.",
 .m_size = -1,
};

PyMODINIT_FUNC
PyInit_custom(void)
{
 PyObject *m;
 if (PyType_Ready(&CustomType) < 0)
 return NULL;

 m = PyModule_Create(&custommodule);
 if (m == NULL)
 return NULL;

 Py_INCREF(&CustomType);
 PyModule_AddObject(m, "Custom", (PyObject *) &CustomType);
 return m;
}