text: const tilebelt = require('@mapbox/tilebelt')
  const fs = require('fs')
  
  const list = require('./nfm.json').nfm
  let geojson = {
    type: 'FeatureCollection', features: []
  }
  
  for (let zxy of list) {
    geojson.features.push({
      type: 'Feature',
      geometry: tilebelt.tileToGeoJSON([zxy[1], zxy[2], zxy[0]]),
      properties: { zxy: zxy.join('-') }
    })
  }
  
  console.log(JSON.stringify(geojson, null, 2))
  