How to use the cronstrue.toString function in cronstrue

export function mapCronToHourFormat(cronExpression) {
    try {
        cronstrue.toString(cronExpression);
    } catch (_) {
        return null;
    }

    const cronParts = cronExpression.split(' ');
    if (cronParts.length === 6) {
        // disregard seconds component
        cronParts.shift();
    }
    const [cronMinute, cronHour, cronDayOfMonth, cronMonth, cronDaysOfWeek] = cronParts;

    const time = {};
    time.minute = cronMinute.includes('*') ? 0 : Number(cronMinute);
    time.date = cronDayOfMonth.includes('*') ? 1 : Number(cronDayOfMonth);
    time.month = cronMonth.includes('*') ? 1 : Number(cronMonth);
    time.days = cronDaysOfWeek.includes('*') ? ['MON'] : cronDaysOfWeek.split(',');

getData: ({status, spec, metadata }) => {
      return [
        ['Created:', `${metadata.creationTimestamp} ( ${toHumanizedAge(metadata.creationTimestamp)} ago )`],
        ['Schedule:', `${spec.schedule} ( ${cronstrue.toString(spec.schedule)} )`],
        ['Concurrency Policy:', spec.concurrencyPolicy],
        ['Suspend', spec.suspend],
        // ['Starting Deadline Seconds:', spec.startingDeadlineSeconds || ''],
        ['Selector:', (spec.selector && spec.selector.matchLabels) || ''],
        ['Parallelism:', spec.parallelism || ''],
        ['Last Schedule Time:', status.lastScheduleTime],
        //Completions:			 // => need to get details of owned Jobs for this...
      ]
    },
  },

export function validateRollupCron(rollupCron) {
  if (!rollupCron || !rollupCron.trim()) {
    return [
      ,
    ];
  }

  try {
    cronstrue.toString(rollupCron);
  } catch (error) {
    const prefix = 'Error: ';
    const prefixIndex = error.indexOf(prefix);

    // Note: cronstrue ships with a localizable version. Refer to the docs for more
    // info on how we can display a localized error value.
    return error.substring(prefixIndex + prefix.length);
  }

  return undefined;
}

preview: function() {
				return this.manual ? 'Imports will run manually' : cronstrue.toString(this.expression)
			}
		},

export function getReadableCronDescriptor(expression) {
  return cronstrue.toString(expression);
}

export const getTimeFromCronExpr = (cronValue) => {
  let result;
  try {
    result = cronstrue.toString(cronValue)
  } catch (err) {
  }
  return result || ''
};

const getNaturalLanguageCronString = (cronSchedule: string) => {
    try {
      return cronstrue.toString(cronSchedule);
    } catch {
      return "Invalid cron string";
    }
  };

Object.entries(requirements[`procs-${name}`]).forEach(([proc, ext]) => {
        if (ext.type === 'cron') {
          res.push([name, proc, `taskcluster.${name}`, ext.deadline, cronstrue.toString(ext.schedule)]);
        }
        if (ext.type === 'background' && ext.subType === 'iterate') {
          res.push([name, proc, `taskcluster.${name}`, 'continuous', 'continuous']);
        }
      });

function cronValidator (value, allState) {
  if (isRequired(value) && !allState.run_immediately) {
    return 'Required if run immediately is unchecked'
  }
  if(value){
    try {
      cronstrue.toString(value)
    } catch (err) {
      return 'illegal cron input'
    }
  }
}
function emailsValidator () {

export function getReadableCronDescriptor(expression) {
  if (expression == "@hourly") {
    expression = "0 * * * *"
  } else if (expression == "@daily") {
    expression = "0 0 * * *"
  } else if (expression == "@weekly") {
    expression = "0 0 * * 0"
  }
  return cronstrue.toString(expression);
}