code: def lookup_bg_color(self, bg_color):
          
          # Background.
          if bg_color in BG_ANSI_COLORS:
              return BG_ANSI_COLORS[bg_color]
          else:
              return self._color_indexes(bg_color)[1]
docs: Return the color for use in the
          `windll.kernel32.SetConsoleTextAttribute` API call.
  
          :param bg_color: Background as text. E.g. 'ffffff' or 'red'