c.NotebookApp.ip = '0.0.0.0'
c.NotebookApp.open_browser = False
c.NotebookApp.port = 8888
c.NotebookApp.password = 'sha1:6c132ae43f5c:4b4cf1efc42fba2c1480e3283c6bcb9769313bdb'

root@VM-0-5-ubuntu:~# firewall-cmd --state
running
root@VM-0-5-ubuntu:~# systemctl stop firewalld.service
root@VM-0-5-ubuntu:~# systemctl disable firewalld.service 
Synchronizing state of firewalld.service with SysV service script with /lib/systemd/systemd-sysv-install.
Executing: /lib/systemd/systemd-sysv-install disable firewalld
Removed /etc/systemd/system/dbus-org.fedoraproject.FirewallD1.service.