s7 enumerate extract information from first szl request

[stze]

After sending the Read_SZL request, only the protocol_id is checked. After that, the same packet is send a second time. Then the response gets parsed for basic hardware information.

 -- send and receive the READ_SZL packet
  response  = send_receive(sock, Read_SZL)
  local pos, protocol_id = bin.unpack("C", response, 8)
  -- if protocol ID is not 0x32 then return nil
  if ( protocol_id ~= 0x32) then
    return nil
  end
  -- send and receive the first SZL Request packet
  response  = send_receive(sock, first_SZL_Request)
-- parse the response for basic hardware information
  output = parse_response(response, host, port, output)

why not extract the hardware information from the first received response?