docs: def main():
      """Builds a yaml file"""
      parser = argparse.ArgumentParser(description='Compose a yaml file.')
      parser.add_argument(
          'root',
          type=argparse.FileType('r'),
          help='The root yaml file to compose.'
      )
  
      args = parser.parse_args()
  
      result = yaml.load(args.root, Loader=ComposeLoader)
  
      print(yaml.dump(result))