code: def to_native(key):
      
      item = find(whatever=key)
      if not item:
          raise NonExistentLanguageError('Language does not exist.')
      return item[u'native']
docs: Find the native name for the language specified by key.
  
      >>> to_native('br')
      u'brezhoneg'
      >>> to_native('sw')
      u'Kiswahili'