Hi very nice work, i try to run Piston on a Raspberry Pi it installed without problem, but it generates this when i try to add my key, any suggestions what's happening and how it can be solved ?

pi@raspberrypi:~ $ piston addkey
Traceback (most recent call last):
File "/usr/local/bin/piston", line 5, in < module >
from pkg_resources import load_entry_point
File "/usr/lib/python3/dist-packages/pkg_resources.py", line 2876, in <
module >
working_set = WorkingSet._build_master()
File "/usr/lib/python3/dist-packages/pkg_resources.py", line 449, in _build_master
ws.require(requires)
File "/usr/lib/python3/dist-packages/pkg_resources.py", line 745, in require
needed = self.resolve(parse_requirements(requirements))
File "/usr/lib/python3/dist-packages/pkg_resources.py", line 639, in resolve
raise DistributionNotFound(req)
pkg_resources.DistributionNotFound: appdirs>=1.4.0

if i check the python version im running, with python -V

Python 2.79

if i do a install of python3 it says Python is already the latest version