How to use the livelossplot.core.NEPTUNE_TARGET function in livelossplot

def _validate_target(self):
        assert isinstance(self.target, str),\
            'target must be str, got "{}" instead.'.format(type(self.target))
        if self.target != MATPLOTLIB_TARGET and self.target != NEPTUNE_TARGET:
            raise ValueError('Target must be "{}" or "{}", got "{}" instead.'.format(MATPLOTLIB_TARGET, NEPTUNE_TARGET, self.target))

draw_plot(self.logs, self.base_metrics,
                      figsize=self.figsize,
                      max_epoch=self.max_epoch,
                      max_cols=self.max_cols,
                      series_fmt=self.series_fmt,
                      metric2title=self.metric2title,
                      skip_first=self.skip_first,
                      extra_plots=self.extra_plots,
                      fig_path=self.fig_path)
            if self.metrics_extrema:
                print_extrema(self.logs,
                              self.base_metrics,
                              self.metrics_extrema,
                              series_fmt=self.series_fmt,
                              metric2title=self.metric2title)
        if self.target == NEPTUNE_TARGET:
            from .neptune_integration import neptune_send_plot
            neptune_send_plot(self.logs)