Import error for straight.plugin.manager

[tombeers]

I know this was meant to be fixed in 1.4.1, but I'm still getting this error, unless I switch back to 1.4.0-post-1 (both installed with pip in a venv):

>>> import straight.plugin
>>> import straight.plugin.manager
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ModuleNotFoundError: No module named 'straight.plugin.manager'

I'm using Python 3.6.1, compiled from source, on Debian Jessie.

Thanks regardless though, great package