[libvirt-users] username and passwd after create VM from XML dump

Good afternoon guys, I created the VM from XML dump, # virsh create vm4.xml and # virsh list I can see the VM running, and I know the ip address for the VM, but how can I know the username and password to login the running VM, which is created from XML dump? is there any place to edit and add the username and password in guest domain XML ? thanks a lot!! Best, Yuanzhen