The attached python script allows you to start a Qemu in a screen with separated screen windows for qemu monitor and for serial port.
It takes care of creating a new screen session if needed. If launched from an existing screen, it will simply add new tabs for the serial port and the monitor. You need to specify the qemu binary to launch, since the wrapper just add the necessary options to the qemu line. It doesn't close the screen, so you can look at what qemu wrote on its output.
Basic usage :
qemu-wrapper qemu -hda vm.img -nographic