pytest error

~/c/nixpkgs> nix-build -A python3Packages.deeplabcut
these derivations will be built:
  /nix/store/6m1hr1ckq6gh5dj7xxqyw8m9yfrvngzl-python3.7-deeplabcut-2.0.5.drv
building '/nix/store/6m1hr1ckq6gh5dj7xxqyw8m9yfrvngzl-python3.7-deeplabcut-2.0.5.drv'...
unpacking sources
unpacking source archive /nix/store/3k7ql5gd6b9rk04f8mgv66919arh22kd-deeplabcut-2.0.5.tar.gz
source root is pytest-3.3.1
setting SOURCE_DATE_EPOCH to timestamp 1512506520 of file pytest-3.3.1/setup.cfg
patching sources
configuring
building
running bdist_wheel
running build
running build_py
creating build
creating build/lib
copying pytest.py -> build/lib
creating build/lib/_pytest
copying _pytest/terminal.py -> build/lib/_pytest
copying _pytest/runner.py -> build/lib/_pytest
copying _pytest/_version.py -> build/lib/_pytest
copying _pytest/compat.py -> build/lib/_pytest
copying _pytest/fixtures.py -> build/lib/_pytest
copying _pytest/tmpdir.py -> build/lib/_pytest
copying _pytest/unittest.py -> build/lib/_pytest
copying _pytest/python.py -> build/lib/_pytest
copying _pytest/resultlog.py -> build/lib/_pytest
copying _pytest/pytester.py -> build/lib/_pytest
copying _pytest/debugging.py -> build/lib/_pytest
copying _pytest/warnings.py -> build/lib/_pytest
copying _pytest/freeze_support.py -> build/lib/_pytest
copying _pytest/config.py -> build/lib/_pytest
copying _pytest/helpconfig.py -> build/lib/_pytest
copying _pytest/junitxml.py -> build/lib/_pytest
copying _pytest/hookspec.py -> build/lib/_pytest
copying _pytest/monkeypatch.py -> build/lib/_pytest
copying _pytest/mark.py -> build/lib/_pytest
copying _pytest/_argcomplete.py -> build/lib/_pytest
copying _pytest/nodes.py -> build/lib/_pytest
copying _pytest/nose.py -> build/lib/_pytest
copying _pytest/pastebin.py -> build/lib/_pytest
copying _pytest/setuponly.py -> build/lib/_pytest
copying _pytest/cacheprovider.py -> build/lib/_pytest
copying _pytest/setupplan.py -> build/lib/_pytest
copying _pytest/python_api.py -> build/lib/_pytest
copying _pytest/skipping.py -> build/lib/_pytest
copying _pytest/outcomes.py -> build/lib/_pytest
copying _pytest/deprecated.py -> build/lib/_pytest
copying _pytest/logging.py -> build/lib/_pytest
copying _pytest/__init__.py -> build/lib/_pytest
copying _pytest/recwarn.py -> build/lib/_pytest
copying _pytest/capture.py -> build/lib/_pytest
copying _pytest/doctest.py -> build/lib/_pytest
copying _pytest/main.py -> build/lib/_pytest
creating build/lib/_pytest/assertion
copying _pytest/assertion/rewrite.py -> build/lib/_pytest/assertion
copying _pytest/assertion/util.py -> build/lib/_pytest/assertion
copying _pytest/assertion/truncate.py -> build/lib/_pytest/assertion
copying _pytest/assertion/__init__.py -> build/lib/_pytest/assertion
creating build/lib/_pytest/_code
copying _pytest/_code/source.py -> build/lib/_pytest/_code
copying _pytest/_code/_py2traceback.py -> build/lib/_pytest/_code
copying _pytest/_code/code.py -> build/lib/_pytest/_code
copying _pytest/_code/__init__.py -> build/lib/_pytest/_code
installing to build/bdist.linux-x86_64/wheel
running install
running install_lib
creating build/bdist.linux-x86_64
creating build/bdist.linux-x86_64/wheel
creating build/bdist.linux-x86_64/wheel/_pytest
copying build/lib/_pytest/terminal.py -> build/bdist.linux-x86_64/wheel/_pytest
copying build/lib/_pytest/runner.py -> build/bdist.linux-x86_64/wheel/_pytest
copying build/lib/_pytest/_version.py -> build/bdist.linux-x86_64/wheel/_pytest
copying build/lib/_pytest/compat.py -> build/bdist.linux-x86_64/wheel/_pytest
copying build/lib/_pytest/fixtures.py -> build/bdist.linux-x86_64/wheel/_pytest
copying build/lib/_pytest/tmpdir.py -> build/bdist.linux-x86_64/wheel/_pytest
copying build/lib/_pytest/unittest.py -> build/bdist.linux-x86_64/wheel/_pytest
copying build/lib/_pytest/python.py -> build/bdist.linux-x86_64/wheel/_pytest
copying build/lib/_pytest/resultlog.py -> build/bdist.linux-x86_64/wheel/_pytest
copying build/lib/_pytest/pytester.py -> build/bdist.linux-x86_64/wheel/_pytest
copying build/lib/_pytest/debugging.py -> build/bdist.linux-x86_64/wheel/_pytest
creating build/bdist.linux-x86_64/wheel/_pytest/_code
copying build/lib/_pytest/_code/source.py -> build/bdist.linux-x86_64/wheel/_pytest/_code
copying build/lib/_pytest/_code/_py2traceback.py -> build/bdist.linux-x86_64/wheel/_pytest/_code
copying build/lib/_pytest/_code/code.py -> build/bdist.linux-x86_64/wheel/_pytest/_code
copying build/lib/_pytest/_code/__init__.py -> build/bdist.linux-x86_64/wheel/_pytest/_code
copying build/lib/_pytest/warnings.py -> build/bdist.linux-x86_64/wheel/_pytest
copying build/lib/_pytest/freeze_support.py -> build/bdist.linux-x86_64/wheel/_pytest
copying build/lib/_pytest/config.py -> build/bdist.linux-x86_64/wheel/_pytest
copying build/lib/_pytest/helpconfig.py -> build/bdist.linux-x86_64/wheel/_pytest
copying build/lib/_pytest/junitxml.py -> build/bdist.linux-x86_64/wheel/_pytest
copying build/lib/_pytest/hookspec.py -> build/bdist.linux-x86_64/wheel/_pytest
copying build/lib/_pytest/monkeypatch.py -> build/bdist.linux-x86_64/wheel/_pytest
copying build/lib/_pytest/mark.py -> build/bdist.linux-x86_64/wheel/_pytest
copying build/lib/_pytest/_argcomplete.py -> build/bdist.linux-x86_64/wheel/_pytest
copying build/lib/_pytest/nodes.py -> build/bdist.linux-x86_64/wheel/_pytest
copying build/lib/_pytest/nose.py -> build/bdist.linux-x86_64/wheel/_pytest
copying build/lib/_pytest/pastebin.py -> build/bdist.linux-x86_64/wheel/_pytest
copying build/lib/_pytest/setuponly.py -> build/bdist.linux-x86_64/wheel/_pytest
copying build/lib/_pytest/cacheprovider.py -> build/bdist.linux-x86_64/wheel/_pytest
copying build/lib/_pytest/setupplan.py -> build/bdist.linux-x86_64/wheel/_pytest
copying build/lib/_pytest/python_api.py -> build/bdist.linux-x86_64/wheel/_pytest
copying build/lib/_pytest/skipping.py -> build/bdist.linux-x86_64/wheel/_pytest
copying build/lib/_pytest/outcomes.py -> build/bdist.linux-x86_64/wheel/_pytest
copying build/lib/_pytest/deprecated.py -> build/bdist.linux-x86_64/wheel/_pytest
copying build/lib/_pytest/logging.py -> build/bdist.linux-x86_64/wheel/_pytest
copying build/lib/_pytest/__init__.py -> build/bdist.linux-x86_64/wheel/_pytest
creating build/bdist.linux-x86_64/wheel/_pytest/assertion
copying build/lib/_pytest/assertion/rewrite.py -> build/bdist.linux-x86_64/wheel/_pytest/assertion
copying build/lib/_pytest/assertion/util.py -> build/bdist.linux-x86_64/wheel/_pytest/assertion
copying build/lib/_pytest/assertion/truncate.py -> build/bdist.linux-x86_64/wheel/_pytest/assertion
copying build/lib/_pytest/assertion/__init__.py -> build/bdist.linux-x86_64/wheel/_pytest/assertion
copying build/lib/_pytest/recwarn.py -> build/bdist.linux-x86_64/wheel/_pytest
copying build/lib/_pytest/capture.py -> build/bdist.linux-x86_64/wheel/_pytest
copying build/lib/_pytest/doctest.py -> build/bdist.linux-x86_64/wheel/_pytest
copying build/lib/_pytest/main.py -> build/bdist.linux-x86_64/wheel/_pytest
copying build/lib/pytest.py -> build/bdist.linux-x86_64/wheel
running install_egg_info
running egg_info
writing pytest.egg-info/PKG-INFO
writing dependency_links to pytest.egg-info/dependency_links.txt
writing entry points to pytest.egg-info/entry_points.txt
writing requirements to pytest.egg-info/requires.txt
writing top-level names to pytest.egg-info/top_level.txt
reading manifest file 'pytest.egg-info/SOURCES.txt'
writing manifest file 'pytest.egg-info/SOURCES.txt'
Copying pytest.egg-info to build/bdist.linux-x86_64/wheel/pytest-3.3.1-py3.7.egg-info
running install_scripts
creating build/bdist.linux-x86_64/wheel/pytest-3.3.1.dist-info/WHEEL
creating 'dist/pytest-3.3.1-py2.py3-none-any.whl' and adding 'build/bdist.linux-x86_64/wheel' to it
adding 'pytest.py'
adding '_pytest/__init__.py'
adding '_pytest/_argcomplete.py'
adding '_pytest/_version.py'
adding '_pytest/cacheprovider.py'
adding '_pytest/capture.py'
adding '_pytest/compat.py'
adding '_pytest/config.py'
adding '_pytest/debugging.py'
adding '_pytest/deprecated.py'
adding '_pytest/doctest.py'
adding '_pytest/fixtures.py'
adding '_pytest/freeze_support.py'
adding '_pytest/helpconfig.py'
adding '_pytest/hookspec.py'
adding '_pytest/junitxml.py'
adding '_pytest/logging.py'
adding '_pytest/main.py'
adding '_pytest/mark.py'
adding '_pytest/monkeypatch.py'
adding '_pytest/nodes.py'
adding '_pytest/nose.py'
adding '_pytest/outcomes.py'
adding '_pytest/pastebin.py'
adding '_pytest/pytester.py'
adding '_pytest/python.py'
adding '_pytest/python_api.py'
adding '_pytest/recwarn.py'
adding '_pytest/resultlog.py'
adding '_pytest/runner.py'
adding '_pytest/setuponly.py'
adding '_pytest/setupplan.py'
adding '_pytest/skipping.py'
adding '_pytest/terminal.py'
adding '_pytest/tmpdir.py'
adding '_pytest/unittest.py'
adding '_pytest/warnings.py'
adding '_pytest/_code/__init__.py'
adding '_pytest/_code/_py2traceback.py'
adding '_pytest/_code/code.py'
adding '_pytest/_code/source.py'
adding '_pytest/assertion/__init__.py'
adding '_pytest/assertion/rewrite.py'
adding '_pytest/assertion/truncate.py'
adding '_pytest/assertion/util.py'
adding 'pytest-3.3.1.dist-info/LICENSE'
adding 'pytest-3.3.1.dist-info/METADATA'
adding 'pytest-3.3.1.dist-info/WHEEL'
adding 'pytest-3.3.1.dist-info/entry_points.txt'
adding 'pytest-3.3.1.dist-info/top_level.txt'
adding 'pytest-3.3.1.dist-info/RECORD'
removing build/bdist.linux-x86_64/wheel
installing
/build/pytest-3.3.1/dist /build/pytest-3.3.1
Processing ./pytest-3.3.1-py2.py3-none-any.whl
Requirement already satisfied: py>=1.5.0 in /nix/store/wr46k137djljql2ai52ghabf2k1iya0b-python3.7-py-1.7.0/lib/python3.7/site-packages (from pytest==3.3.1) (1.7.0)
Collecting pluggy<0.7,>=0.5 (from pytest==3.3.1)
  Could not find a version that satisfies the requirement pluggy<0.7,>=0.5 (from pytest==3.3.1) (from versions: )
No matching distribution found for pluggy<0.7,>=0.5 (from pytest==3.3.1)
builder for '/nix/store/6m1hr1ckq6gh5dj7xxqyw8m9yfrvngzl-python3.7-deeplabcut-2.0.5.drv' failed with exit code 1
error: build of '/nix/store/6m1hr1ckq6gh5dj7xxqyw8m9yfrvngzl-python3.7-deeplabcut-2.0.5.drv' failed