code: def combine_focus_with_next(self):
          
  
          below, ignore = self.get_next(self.focus)
          if below is None:
              # already at bottom
              return
  
          focus = self.lines[self.focus]
          focus.set_edit_text(focus.edit_text + below.edit_text)
          del self.lines[self.focus + 1]
docs: Combine the focus edit widget with the one below.