def _get_delta(self, name):
        r"""Returns the raw moments that were accumulated for the given
        statistic between the last two calls to `update()`, or zero if
        no scalars were collected.
        """
        assert self._regex.fullmatch(name)
        if name not in self._moments:
            self._moments[name] = torch.zeros([_num_moments], dtype=_counter_dtype)
        return self._moments[name]
Returns the raw moments that were accumulated for the given
        statistic between the last two calls to `update()`, or zero if
        no scalars were collected.
        
converters/stylegan2ada_pth_official/torch_utils/training_stats.py