Change all users with specific role to another role across MU network with WP-CLI

gistfile1.txt

for i in $(sudo -u www-data wp site list --field=url); \
do
 echo ${i}; \
 a="$(sudo -u www-data wp user list --url=${i} --role=SuperUser --field=user_login)"; \
  if [[ ! -z "${a}" ]]; then \
   sudo -u www-data wp user --url="${i}" update "${a}" --role "administrator"; \
   echo "User ${a} updated for site ${i}."; \
  fi; \
done