#include <Python.h>

static PyObject *get_even(PyObject *self, PyObject *args){

/*

The function PyArg_ParseTuple() in the Python API

checks the argument types and converts them to C values.

PyArg_ParseTuple() returns true (nonzero)

O - get one argument as a sequence

*/

PyObject *listObj;

if(!PyArg_ParseTuple(args, "O", &listObj)){

return 0;

}

listObj = PySequence_Fast(listObj, "argument must be iterable");

if(!listObj)

return 0;

int nums_len = PyList_Size(listObj);

printf("List size = %d\n", nums_len);

PyObject *even_nums = PyList_New(0);

for(int i=0; i<nums_len; i++){

PyLongObject *item = PyList_GetItem(listObj, i);

long num = PyLong_AsLong(item);

int vOut = (int)num;

printf("index = %d | value = %d\n", i, vOut);

if(vOut % 2 == 0){

PyList_Append(even_nums, Py_BuildValue("i", vOut));

}

}

return even_nums;

}

static PyMethodDef DemoMethods[] = {

{"get_even", get_even, METH_VARARGS, "Find even numbers from given list"},

{NULL, NULL, 0, NULL} /* Sentinel */

};

static struct PyModuleDef my_demo_module = {

PyModuleDef_HEAD_INIT,

"my_demo_module", /* name of module and should be same as funnction */

"Module docs", /* module documentation, may be NULL */

-1, /* size of per-interpreter state of the module or -1 if the module keeps state in global variables. */

DemoMethods

};

PyMODINIT_FUNC PyInit_my_demo_module(void) {

PyObject *module = PyModule_Create(&my_demo_module);

return module;

}