How to Set mac address as host name and hosts 127.0.1.1

Question

I'm using Ubuntu for my OS and I'm struggling to set my host name and hosts to a mac address automatically any help on this would be great.

NAME=$GATEWAY_MAC| sed s/://g
hostnamectl set-hostname $NAME
sed -i '2d' /etc/hosts
ed /etc/hosts <<-'EOF'
/127.0.0.1/a 127.0.1.1 $NAME 
. wq
EOF
cat /etc/hostname cat /etc/hosts