i can't deploy devstack on a clear ubuntu 18.04

[saltfisher]

first, i install a ubuntu 18.04 in a VMware player.
then,i follow the quick start page to prepare related environments step by step.
after i execute ./stack.sh, i can't deploy it successfully.
my encountered first issue was stack can't access /opt/stack/.cache, then i give him permission.
my encountered second issue was ‘/opt/stack/requirements/.venv/bin/pip’: No such file or directory.
who can tell me how can i solve this issue, thanks.

[Dr. Jens Harbott (j-harbott)]

This sounds like an issue that may happen when you are using multiple accounts. Try removing /opt/stack completely and starting again, or retry from a fresh new instance.

[Launchpad Janitor (janitor)]

[Expired for devstack because there has been no activity for 60 days.]