code: def launch_help(self, helpname, filename):
          
  
          # Set up window
  
          position = config["help_window_position"]
          size = config["help_window_size"]
  
          self.help_window = wx.Frame(self.main_window, -1,
                                      helpname, position, size)
          self.help_htmlwindow = wx.html.HtmlWindow(self.help_window, -1,
                                                    (0, 0), size)
  
          self.help_window.Bind(wx.EVT_MOVE, self.OnHelpMove)
          self.help_window.Bind(wx.EVT_SIZE, self.OnHelpSize)
          self.help_htmlwindow.Bind(wx.EVT_RIGHT_DOWN, self.OnHelpBack)
          self.help_htmlwindow.Bind(wx.html.EVT_HTML_LINK_CLICKED,
                                    lambda e: self.open_external_links(e))
          self.help_htmlwindow.Bind(wx.EVT_MOUSEWHEEL,
                                    lambda e: self.zoom_html(e))
  
          # Get help data
          current_path = os.getcwd()
          os.chdir(get_help_path())
  
          try:
              if os.path.isfile(filename):
                  self.help_htmlwindow.LoadFile(filename)
  
              else:
                  self.help_htmlwindow.LoadPage(filename)
  
          except IOError:
              self.help_htmlwindow.LoadPage(filename)
  
          # Show tutorial window
  
          self.help_window.Show()
  
          os.chdir(current_path)
docs: Generic help launcher
  
          Launches HTMLWindow that shows content of filename
          or the Internet page with the filename url
  
          Parameters
          ----------
  
          filename: String
          \thtml file or url