How to use the style-dictionary.registerTransformGroup function in style-dictionary

// console.log(StyleDictionary.transformGroup['group_name']);

StyleDictionary.registerTransformGroup({
  name: 'custom/web',
  // notice: here the "size/px" transform is not the pre-defined one, but the custom one we have declared above
  transforms: ['attribute/cti', 'name/cti/constant', 'size/px', 'color/css', 'time/seconds', 'ratio/%']
});

StyleDictionary.registerTransformGroup({
  name: 'custom/scss',
  // this is to show one possibility for adding a few transforms to a pre-defined group
  // (however, we suggest to use the previous approach, which is more explicit and clear)
  transforms: StyleDictionary.transformGroup['scss'].concat(['size/px', 'ratio/%'])
});

StyleDictionary.registerTransformGroup({
  name: 'custom/android',
  // as you can see, here we are completely ignoring the "attribute/cti" transform (it's totally possible),
  // because we are relying on custom attributes for the matchers and the custom format for the output
  transforms: ['name/squiggle', 'hexRGB/hexARGB', 'unitless/dp-sp']
});


// REGISTER A CUSTOM FORMAT (to be used for this specific example)

StyleDictionary.registerFormat({
  name: 'custom/android/xml',
  formatter: function(dictionary) {
    return dictionary.allProperties.map(function(prop) {
      return `${prop.value}`;
    }).join('\n');
  }

transforms: ["attribute/cti", "name/cti/kebab", "size/px", "color/css"]
});

StyleDictionaryPackage.registerTransformGroup({
    name: 'tokens-scss',
    // to see the pre-defined "scss" transformation use: console.log(StyleDictionaryPackage.transformGroup['scss']);
    transforms: [ "name/cti/kebab", "time/seconds", "size/px", "color/css" ]
});

StyleDictionaryPackage.registerTransformGroup({
    name: 'tokens-ios',
    // to see the pre-defined "ios" transformation use: console.log(StyleDictionaryPackage.transformGroup['ios']);
    transforms: [ "attribute/cti", "name/cti/camel", "size/pxToPt"]
});

StyleDictionaryPackage.registerTransformGroup({
    name: 'tokens-android',
    // to see the pre-defined "android" transformation use: console.log(StyleDictionaryPackage.transformGroup['android']);
    transforms: [ "attribute/cti", "name/cti/camel", "size/pxToDp"]
});

StyleDictionaryPackage.transformGroup['android'];

console.log('Build started...');

// PROCESS THE DESIGN TOKENS FOR THE DIFFEREN BRANDS AND PLATFORMS

['web', 'ios', 'android'].map(function(platform) {
    ['brand#1', 'brand#2', 'brand#3'].map(function(brand) {

        console.log('\n==============================================');
        console.log(`\nProcessing: [${platform}] [${brand}]`);