Return a dictionary of statistics collected during creation of the
        model. These statistics are also available with the ``get`` method and
        are described in more detail in that method's documentation.

        Returns
        -------
        out : dict
            Dictionary of statistics compiled during creation of the
            NearestNeighborsModel.

        See Also
        --------
        summary

        Examples
        --------
        >>> sf = turicreate.SFrame({'label': range(3),
        ...                       'feature1': [0.98, 0.62, 0.11],
        ...                       'feature2': [0.69, 0.58, 0.36]})
        >>> model = turicreate.nearest_neighbors.create(sf, 'label')
        >>> model.training_stats()
        {'features': 'feature1, feature2',
         'label': 'label',
         'leaf_size': 1000,
         'num_examples': 3,
         'num_features': 2,
         'num_variables': 2,
         'training_time': 0.023223,
         'tree_depth': 1}

def _training_stats(self):
        """
        Return a dictionary of statistics collected during creation of the
        model. These statistics are also available with the ``get`` method and
        are described in more detail in that method's documentation.

        Returns
        -------
        out : dict
            Dictionary of statistics compiled during creation of the
            NearestNeighborsModel.

        See Also
        --------
        summary

        Examples
        --------
        >>> sf = turicreate.SFrame({'label': range(3),
        ...                       'feature1': [0.98, 0.62, 0.11],
        ...                       'feature2': [0.69, 0.58, 0.36]})
        >>> model = turicreate.nearest_neighbors.create(sf, 'label')
        >>> model.training_stats()
        {'features': 'feature1, feature2',
         'label': 'label',
         'leaf_size': 1000,
         'num_examples': 3,
         'num_features': 2,
         'num_variables': 2,
         'training_time': 0.023223,
         'tree_depth': 1}
        """

        opts = {'model': self.__proxy__, 'model_name': self.__name__}
        return _turicreate.extensions._nearest_neighbors.training_stats(opts)