code: def scroll_down (self): # <ESC>D
          '''Scroll display down one line.'''
  
          # Screen is indexed from 1, but arrays are indexed from 0.
          s = self.scroll_row_start - 1
          e = self.scroll_row_end - 1
          self.w[s+1:e+1] = copy.deepcopy(self.w[s:e]f scroll_down (self): # <ESC>D
          '''Scroll display down one line.'''
  
          # Screen is indexed from 1, but arrays are indexed from 0.
          s = self.scroll_row_start - 1
          e = self.scroll_row_end - 1
          self.w[s+1:e+1] = copy.deepcopy(self.w[s:e])
docs: Scroll display down one line.