code: def get_extract_value_function(column_identifier):
      
      def extract_value(run_result):
          pos = None
          for i, column in enumerate(run_result.columns):
              if column.title == column_identifier:
                  pos = i
                  break
          if pos is None:
              sys.exit('CPU time missing for task {0}.'.format(run_result.task_id[0]))
          return Util.to_decimal(run_result.values[pos])
      return extract_value
docs: returns a function that extracts the value for a column.