Traceback (most recent call last):
File "/usr/bin/certbot", line 5, in <module>
from pkg_resources import load_entry_point
File "/usr/lib/python2.7/site-packages/pkg_resources/__init__.py", line 3138, in <module>
@_call_aside
File "/usr/lib/python2.7/site-packages/pkg_resources/__init__.py", line 3122, in _call_aside
f(*args, **kwargs)
File "/usr/lib/python2.7/site-packages/pkg_resources/__init__.py", line 3151, in _initialize_master_working_set
working_set = WorkingSet._build_master()
File "/usr/lib/python2.7/site-packages/pkg_resources/__init__.py", line 666, in _build_master
return cls._build_from_requirements(__requires__)
File "/usr/lib/python2.7/site-packages/pkg_resources/__init__.py", line 679, in _build_from_requirements
dists = ws.resolve(reqs, Environment())
File "/usr/lib/python2.7/site-packages/pkg_resources/__init__.py", line 867, in resolve
raise DistributionNotFound(req, requirers)
pkg_resources.DistributionNotFound: The 'urllib3<1.23,>=1.21.1' distribution was not found and is required by requests