text: import os
  
  from skyscraper.utils.constants import SPEEDOMETER_KEY, AGE_KEY, PRICE_KEY, POWER_KEY, CURRENCY_KEY
  
  VALIDATION_DATA = {
      'hahu1.html': {
          SPEEDOMETER_KEY: '98 100 km',
          AGE_KEY: '2014/1',
          PRICE_KEY: '8300000',
          POWER_KEY: '190 kW',
          CURRENCY_KEY: 'HUF'
      },
      'hahu2.html': {
          SPEEDOMETER_KEY: '178 000 km',
          AGE_KEY: '2012/7',
          PRICE_KEY: '9200000',
          POWER_KEY: '230 kW',
          CURRENCY_KEY: 'HUF'
      },
      'mobile1.html': {
          SPEEDOMETER_KEY: '56,488 km',
          AGE_KEY: '08/2013',
          PRICE_KEY: '20444',
          POWER_KEY: '165 kW',
          CURRENCY_KEY: 'EUR'
      }
  }
  
  
  def gather_extension_files(root):
      """
      Traverses through all subdirectories of root collecting *.html filenames. Recursive.
      :param root: the basepoint of search
      :rtype: set
      :return: all found js filenames
      """
      extension_files = set()
      for child in os.listdir(root):
          abs_path = os.path.join(root, child)
          if os.path.isdir(abs_path):
              extension_files |= gather_extension_files(abs_path)
          elif child.endswith(".html"):
              extension_files.add(abs_path)
      return extension_files
  