code: def extensions(self):
          
          encoded_extensions = []
          for ext in self._extension_files:
              file_ = open(ext, 'rb')
              # Should not use base64.encodestring() which inserts newlines every
              # 76 characters (per RFC 1521).  Chromedriver has to remove those
              # unnecessary newlines before decoding, causing performance hit.
              encoded_extensions.append(base64.b64encode(file_.read()).decode('UTF-8'))
  
              file_.close()
          return encoded_extensions + self._extensions
docs: :Returns: A list of encoded extensions that will be loaded into chrome