"unexpected keyword argument 'kw_only'"

[juanjo75es]

When I try to run any example I always get that error. For example if I run
stdpopsim HomSap -c chr22 -o foo.ts 2
I get:

Traceback (most recent call last):
File "/home/juanjo/.local/bin/stdpopsim", line 6, in
from stdpopsim.cli import stdpopsim_main
File "/home/juanjo/.local/lib/python3.6/site-packages/stdpopsim/init.py", line 12, in
from . models import * # NOQA
File "/home/juanjo/.local/lib/python3.6/site-packages/stdpopsim/models.py", line 144, in
@attr.s(kw_only=True)
TypeError: attrs() got an unexpected keyword argument 'kw_only'

[andrewkern]

strange. can you post a bit of info about your python install? did you use the pip install?

[gtsambos]

Thanks @juanjo75es! Can you see if you still have this problem after manually upgrading the attrs package?
Eg. if you use pip,

pip install attrs --upgrade

@andrewkern , @jeromekelleher: I think this is to do with this issue, but later versions of attrs have fixed this.