Comment 1 for bug 1677252

Hi John,
I faced the same issue.
Then I realized that my openstack SDK was on 0.9.13

stack@openstack-nti-16:~/python-openstacksdk$ pip freeze | grep openstacksdk
openstacksdk==0.9.13

I upgraded to 0.9.14 , and now:
openstack network auto allocated topology create --check-resources
+---------+-------+
| Field | Value |
+---------+-------+
| dry_run | None |
+---------+-------+

Can you your version of Openstack SDK? I guess you pulled up the master of OSC but not of the SDK, maybe?