Comment 4 for bug 1915400

Here's a simple test case from the virtualenv which shows a failure to call the module using the existing import, and a success using an alternative approach:

root@infra1-nova-api-container-c49119df:~# source /openstack/venvs/nova-22.0.0/bin/activate

(nova-22.0.0) root@infra1-nova-api-container-c49119df:~# python3
Python 3.6.7 (default, Oct 22 2018, 11:32:17)
[GCC 8.2.0] on linux
Type "help", "copyright", "credits" or "license" for more information.

>>> import eventlet
>>> eventlet.tpool.execute
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: module 'eventlet' has no attribute 'tpool'

>>> from eventlet import tpool
>>> tpool.execute
<function execute at 0x7f512ee14ea0>