code: def _host():
      
      host_and_port = request.urlparts[1]
      try:
          host, _ = host_and_port.split(':')
      except ValueError:
          # No port yet. Host defaults to '127.0.0.1' in bottle.request.
          return DEFAULT_BIND
      return host or DEFAULT_BIND
docs: Get the Host from the most recent HTTP request.