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

// REGISTER THE CUSTOM TRANFORM GROUPS

// if you want to see what a pre-defined group contains, uncomment the next line:
// 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) {

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}]`);

        const StyleDictionary = StyleDictionaryPackage.extend(getStyleDictionaryConfig(brand, platform));

        if (platform === 'web') {
            StyleDictionary.buildPlatform('web/js');
            StyleDictionary.buildPlatform('web/json');

// Using the custom format defined above
        format: 'myFormat'
      }]
    },
    css: {
      transformGroup: 'css',
      buildPath: buildPath,
      files: [{
        destination: 'variables.css',
        format: 'css/variables'
      }]
    },

    scss: {
      // This works, we can create new transform arrays on the fly and edit built-ins
      transforms: StyleDictionary.transformGroup.scss.concat('color/rgb'),
      buildPath: buildPath,
      files: [{
        destination: 'variables.scss',
        format: 'scss/variables'
      }]
    },

    js: {
      transforms: StyleDictionary.transformGroup.js.concat('myRegisteredTransform'),
      buildPath: buildPath,
      // If you want to get super fancy, you can use node modules
      // to create a properties object first, and then you can
      // reference attributes of that object. This allows you to
      // output 1 file per color namespace.
      files: Object.keys(properties.color).map((colorType) => ({
        destination: `${colorType}.js`,

format: 'css/variables'
      }]
    },

    scss: {
      // This works, we can create new transform arrays on the fly and edit built-ins
      transforms: StyleDictionary.transformGroup.scss.concat('color/rgb'),
      buildPath: buildPath,
      files: [{
        destination: 'variables.scss',
        format: 'scss/variables'
      }]
    },

    js: {
      transforms: StyleDictionary.transformGroup.js.concat('myRegisteredTransform'),
      buildPath: buildPath,
      // If you want to get super fancy, you can use node modules
      // to create a properties object first, and then you can
      // reference attributes of that object. This allows you to
      // output 1 file per color namespace.
      files: Object.keys(properties.color).map((colorType) => ({
        destination: `${colorType}.js`,
        format: 'javascript/es6',
        // Filters can be functions that return a boolean
        filter: (prop) => prop.attributes.type === colorType
      }))
    },

    // You can still use built-in transformGroups and formats like before
    json: {
      transformGroup: 'js',