virsh net-define --file ABSOLUTE_FILE_PATH
<network> <name>br0</name> <forward mode="bridge"/> <bridge name="br0" /> </network>
<network> <name>examplebridge</name> <forward mode='route'/> <bridge name='kvmbr0' stp='on' delay='0'/> <ip address='192.168.1.11' netmask='255.255.255.0' /> </network>