@staticmethod
def parse_help_line(metric_id, meter_unit):
    """Build the Prometheus HELP line.

        Args:
            metric_id (str): Identifier of the metric.
            meter_unit (str): Unit of the metric.

        Returns:
            str: Prometheus HELP line.
        """
    return f'# HELP {metric_id} units {meter_unit}\n'
