extractHourAndValue = (
  data = [],
  getHour = d => Number(d['hour_of_week']),
  getValue = d => Number(d['value'])
) => {
  return data.map(d => ({
    hour: getHour(d),
    value: getValue(d),
  }));
}
Extract the hour and the value attributes from the given data
@param {array} data - input data of arbitory attributes
@param {func} getHour - accessor function to extract the hour value from a datum
@param {func} getValue - accessor function to extract the metric value from a datum
@return an array of objects only contains hour and value for the downsteam rendering