text: // namespace object implementation
  
  #include "Python.h"
  #include "structmember.h"
  
  
  typedef struct {
      PyObject_HEAD
      PyObject *ns_dict;
  } _PyNamespaceObject;
  
  
  static PyMemberDef namespace_members[] = {
      {"__dict__", T_OBJECT, offsetof(_PyNamespaceObject, ns_dict), READONLY},
      {NULL}
  };
  
  
  // Methods
  
  static PyObject *
  namespace_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
  {
      PyObject *self;
  
      assert(type != NULL && type->tp_alloc != NULL);
      self = type->tp_alloc(type, 0);
      if (self != NULL) {
          _PyNamespaceObject *ns = (_PyNamespaceObject *)self;
          ns->ns_dict = PyDict_New();
          if (ns->ns_dict == NULL) {
              Py_DECREF(ns);
              return NULL;
          }
      }
      return self;
  }
  
  
  static int
  namespace_init(_PyNamespaceObject *ns, PyObject *args, PyObject *kwds)
  {
      // ignore args if it's NULL or empty
      if (args != NULL) {
          Py_ssize_t argcount = PyObject_Size(args);
          if (argcount < 0)
              return -1;
          else if (argcount > 0) {
              PyErr_Format(PyExc_TypeError, "no positional arguments expected");
              return -1;
          }
      }
      if (kwds == NULL) {
          return 0;
      }
      if (!PyArg_ValidateKeywordArguments(kwds)) {
          return -1;
      }
      return PyDict_Update(ns->ns_dict, kwds);
  }
  
  
  static void
  namespace_dealloc(_PyNamespaceObject *ns)
  {
      PyObject_GC_UnTrack(ns);
      Py_CLEAR(ns->ns_dict);
      Py_TYPE(ns)->tp_free((PyObject *)ns);
  }
  
  
  static PyObject *
  namespace_repr(PyObject *ns)
  {
      int i, loop_error = 0;
      PyObject *pairs = NULL, *d = NULL, *keys = NULL, *keys_iter = NULL;
      PyObject *key;
      PyObject *separator, *pairsrepr, *repr = NULL;
      const char * name;
  
      name = (Py_TYPE(ns) == &_PyNamespace_Type) ? "namespace"
                                                 : ns->ob_type->tp_name;
  
      i = Py_ReprEnter(ns);
      if (i != 0) {
          return i > 0 ? PyUnicode_FromFormat("%s(...)", name) : NULL;
      }
  
      pairs = PyList_New(0);
      if (pairs == NULL)
          goto error;
  
      d = ((_PyNamespaceObject *)ns)->ns_dict;
      assert(d != NULL);
      Py_INCREF(d);
  
      keys = PyDict_Keys(d);
      if (keys == NULL)
          goto error;
      if (PyList_Sort(keys) != 0)
          goto error;
  
      keys_iter = PyObject_GetIter(keys);
      if (keys_iter == NULL)
          goto error;
  
      while ((key = PyIter_Next(keys_iter)) != NULL) {
          if (PyUnicode_Check(key) && PyUnicode_GET_LENGTH(key) > 0) {
              PyObject *value, *item;
  
              value = PyDict_GetItem(d, key);
              if (value != NULL) {
                  item = PyUnicode_FromFormat("%S=%R", key, value);
                  if (item == NULL) {
                      loop_error = 1;
                  }
                  else {
                      loop_error = PyList_Append(pairs, item);
                      Py_DECREF(item);
                  }
              }
          }
  
          Py_DECREF(key);
          if (loop_error)
              goto error;
      }
  
      separator = PyUnicode_FromString(", ");
      if (separator == NULL)
          goto error;
  
      pairsrepr = PyUnicode_Join(separator, pairs);
      Py_DECREF(separator);
      if (pairsrepr == NULL)
          goto error;
  
      repr = PyUnicode_FromFormat("%s(%S)", name, pairsrepr);
      Py_DECREF(pairsrepr);
  
  error:
      Py_XDECREF(pairs);
      Py_XDECREF(d);
      Py_XDECREF(keys);
      Py_XDECREF(keys_iter);
      Py_ReprLeave(ns);
  
      return repr;
  }
  
  
  static int
  namespace_traverse(_PyNamespaceObject *ns, visitproc visit, void *arg)
  {
      Py_VISIT(ns->ns_dict);
      return 0;
  }
  
  
  static int
  namespace_clear(_PyNamespaceObject *ns)
  {
      Py_CLEAR(ns->ns_dict);
      return 0;
  }
  
  
  static PyObject *
  namespace_richcompare(PyObject *self, PyObject *other, int op)
  {
      if (PyObject_TypeCheck(self, &_PyNamespace_Type) &&
          PyObject_TypeCheck(other, &_PyNamespace_Type))
          return PyObject_RichCompare(((_PyNamespaceObject *)self)->ns_dict,
                                     ((_PyNamespaceObject *)other)->ns_dict, op);
      Py_RETURN_NOTIMPLEMENTED;
  }
  
  
  PyDoc_STRVAR(namespace_reduce__doc__, "Return state information for pickling");
  
  static PyObject *
  namespace_reduce(_PyNamespaceObject *ns)
  {
      PyObject *result, *args = PyTuple_New(0);
  
      if (!args)
          return NULL;
  
      result = PyTuple_Pack(3, (PyObject *)Py_TYPE(ns), args, ns->ns_dict);
      Py_DECREF(args);
      return result;
  }
  
  
  static PyMethodDef namespace_methods[] = {
      {"__reduce__", (PyCFunction)namespace_reduce, METH_NOARGS,
       namespace_reduce__doc__},
      {NULL,         NULL}  // sentinel
  };
  
  
  PyDoc_STRVAR(namespace_doc,
  "A simple attribute-based namespace.\n\
  \n\
  SimpleNamespace(**kwargs)");
  
  PyTypeObject _PyNamespace_Type = {
      PyVarObject_HEAD_INIT(&PyType_Type, 0)
      "types.SimpleNamespace",                    /* tp_name */
      sizeof(_PyNamespaceObject),                 /* tp_basicsize */
      0,                                          /* tp_itemsize */
      (destructor)namespace_dealloc,              /* tp_dealloc */
      0,                                          /* tp_print */
      0,                                          /* tp_getattr */
      0,                                          /* tp_setattr */
      0,                                          /* tp_reserved */
      (reprfunc)namespace_repr,                   /* tp_repr */
      0,                                          /* tp_as_number */
      0,                                          /* tp_as_sequence */
      0,                                          /* tp_as_mapping */
      0,                                          /* tp_hash */
      0,                                          /* tp_call */
      0,                                          /* tp_str */
      PyObject_GenericGetAttr,                    /* tp_getattro */
      PyObject_GenericSetAttr,                    /* tp_setattro */
      0,                                          /* tp_as_buffer */
      Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC |
          Py_TPFLAGS_BASETYPE,                    /* tp_flags */
      namespace_doc,                              /* tp_doc */
      (traverseproc)namespace_traverse,           /* tp_traverse */
      (inquiry)namespace_clear,                   /* tp_clear */
      namespace_richcompare,                      /* tp_richcompare */
      0,                                          /* tp_weaklistoffset */
      0,                                          /* tp_iter */
      0,                                          /* tp_iternext */
      namespace_methods,                          /* tp_methods */
      namespace_members,                          /* tp_members */
      0,                                          /* tp_getset */
      0,                                          /* tp_base */
      0,                                          /* tp_dict */
      0,                                          /* tp_descr_get */
      0,                                          /* tp_descr_set */
      offsetof(_PyNamespaceObject, ns_dict),      /* tp_dictoffset */
      (initproc)namespace_init,                   /* tp_init */
      PyType_GenericAlloc,                        /* tp_alloc */
      (newfunc)namespace_new,                     /* tp_new */
      PyObject_GC_Del,                            /* tp_free */
  };
  
  
  PyObject *
  _PyNamespace_New(PyObject *kwds)
  {
      PyObject *ns = namespace_new(&_PyNamespace_Type, NULL, NULL);
      if (ns == NULL)
          return NULL;
  
      if (kwds == NULL)
          return ns;
      if (PyDict_Update(((_PyNamespaceObject *)ns)->ns_dict, kwds) != 0) {
          Py_DECREF(ns);
          return NULL;
      }
  
      return (PyObject *)ns;
  }
  