def op_for_measurement(measure)
      stat = measure.id.tags.fetch(:statistic, :unknown)
      OPS.fetch(stat, UNKNOWN_OP)
    end
def op_for_measurement(measure)
      stat = measure.id.tags.fetch(:statistic, :unknown)
      OPS.fetch(stat, UNKNOWN_OP)
    end
Get the operation to be used for the given Measure
 Gauges are aggregated using MAX_OP, counters with ADD_OP