code: def check_for_connection(self):
          
          for idx, arg in enumerate(self.args):
              if arg.startswith('@'):
                  if arg[1:] not in config.connections:
                      self.parser.error("Undefined connection '{}'!".format(arg[1:]))
                  config.scgi_url = config.connections[arg[1:]]
                  self.LOG.debug("Switched to connection %s (%s)", arg[1:], config.scgi_url)
                  del self.args[idx]
                  break
docs: Scan arguments for a `@name` one.