Description of problem:
flake8 --config=scripts/flake8.cfg test/zdtm.py
Traceback (most recent call last):
  File "/usr/lib/python3.6/site-packages/pkg_resources/__init__.py", line 666, in _build_master
    ws.require(__requires__)
  File "/usr/lib/python3.6/site-packages/pkg_resources/__init__.py", line 984, in require
    needed = self.resolve(parse_requirements(requirements))
  File "/usr/lib/python3.6/site-packages/pkg_resources/__init__.py", line 875, in resolve
    raise VersionConflict(dist, req).with_context(dependent_req)
pkg_resources.ContextualVersionConflict: (pycodestyle 2.4.0 (/usr/lib/python3.6/site-packages), Requirement.parse('pycodestyle<2.4.0,>=2.0.0'), {'flake8'})

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/bin/flake8", line 6, in <module>
    from pkg_resources import load_entry_point
  File "/usr/lib/python3.6/site-packages/pkg_resources/__init__.py", line 3147, in <module>
    @_call_aside
  File "/usr/lib/python3.6/site-packages/pkg_resources/__init__.py", line 3131, in _call_aside
    f(*args, **kwargs)
  File "/usr/lib/python3.6/site-packages/pkg_resources/__init__.py", line 3160, in _initialize_master_working_set
    working_set = WorkingSet._build_master()
  File "/usr/lib/python3.6/site-packages/pkg_resources/__init__.py", line 668, in _build_master
    return cls._build_from_requirements(__requires__)
  File "/usr/lib/python3.6/site-packages/pkg_resources/__init__.py", line 681, in _build_from_requirements
    dists = ws.resolve(reqs, Environment())
  File "/usr/lib/python3.6/site-packages/pkg_resources/__init__.py", line 870, in resolve
    raise DistributionNotFound(req, requirers)
pkg_resources.DistributionNotFound: The 'pycodestyle<2.4.0,>=2.0.0' distribution was not found and is required by flake8
make: *** [Makefile:380: lint] Error 1
make: *** [fedora-rawhide] Error 2
make: Leaving directory `/home/travis/build/avagin/criu/scripts/travis'


Version-Release number of selected component (if applicable):


How reproducible:
100%


Steps to Reproduce:
1. yum install python3-flake8
2. git clone https://github.com/xemul/criu
3. cd criu
4. make lint