code: def register(self, server_info):
          
          # Path relative to the server directory
          self.path = os.path.relpath(self.filename,
                                      start=server_info['notebook_dir'])
  
          # Replace backslashes on Windows
          if os.name == 'nt':
              self.path = self.path.replace('\\', '/')
  
          # Server url to send requests to
          self.server_url = server_info['url']
  
          # Server token
          self.token = server_info['token']
  
          url = url_path_join(self.server_url, 'notebooks',
                              url_escape(self.path))
  
          # Set file url to load this notebook
          self.file_url = self.add_token(url)
docs: Register attributes that can be computed with the server info.