code: def __on_help_online_manual(event):
      webbrowser.open(cellprofiler.gui.help.content.MANUAL_URL)
  
imports: import webbrowser
  import wx.adv
  from cellprofiler.gui.dialog import AboutDialogInfo
  import cellprofiler.gui.help.content
  import cellprofiler.gui.help.search
  import cellprofiler.gui.htmldialog
  import cellprofiler.gui.menu
label_desc: Use image node_id 8 for calling the Menu obj's underlying member method code with example usage: obj.__on_help_online_manual(event) without return types