text: from .metric import Metric
  from .tsv_metric import TSVMetric
  
  class PercentTarget20x(Metric[float], TSVMetric):
  
      def value(self, metrics_dir: str) -> float:
          value = self.extract_metric(metrics_dir)
          return float(value)
  
      def name(self) -> str:
          return 'PCT_TARGET_BASES_20X'
  
      def metric_column_name(self) -> str:
          return self.name()
  
      def metric_file_pattern(self) -> str:
          return rf".+/{self.sample_id}\.hs_metrics"
  
      def take_first_value(self) -> bool:
          return True
  