code: def free(self):
          
          data = WebDavXmlUtils.create_free_space_request_content()
          response = self.execute_request(action='free', path='', data=data)
          return WebDavXmlUtils.parse_free_space_response(response.content, self.webdav.hostname)
docs: Returns an amount of free space on remote WebDAV server.
          More information you can find by link http://webdav.org/specs/rfc4918.html#METHOD_PROPFIND
  
          :return: an amount of free space in bytes.