shell:$ nslookup -timeout=2 -retry=1 'sixproxy.herokuapp.com'
Server:		127.0.0.53
Address:	127.0.0.53#53

Non-authoritative answer:
sixproxy.herokuapp.com	canonical name = ie01.ingress.herokuapp.com.
Name:	ie01.ingress.herokuapp.com
Address: 34.241.115.67
Name:	ie01.ingress.herokuapp.com
Address: 54.78.134.111
Name:	ie01.ingress.herokuapp.com
Address: 54.228.42.199