code: def handle_parse_result(self, ctx, opts, args):
          
          if 'sclize' in opts and not SclConvertor:
              raise click.UsageError("Please install spec2scl package to "
                                     "perform SCL-style conversion")
          if self.name in opts and 'sclize' not in opts:
              raise click.UsageError(
                  "`--{}` can only be used with --sclize option".format(
                      self.name))
  
          return super(SclizeOption, self).handle_parse_result(ctx, opts, args)
docs: Validate SCL related options before parsing.