% pwd
~proj/misc/git-xltrail
% python3 --version
Python 3.5.3

% virtualenv -p $(which python3) venv
Already using interpreter /usr/bin/python3
Using base prefix '/usr'
New python executable in /home/jkirk/projects/misc/git-xltrail/venv/bin/python3
Also creating executable in /home/jkirk/projects/misc/git-xltrail/venv/bin/python
Installing setuptools, pkg_resources, pip, wheel...done.

% . venv/bin/activate
% pip install -r requirements.txt

% pip install -r requirements.txt
Collecting colorama==0.3.9 (from -r requirements.txt (line 1))
  Using cached https://files.pythonhosted.org/packages/db/c8/7dcf9dbcb22429512708fe3a547f8b6101c0d02137acbd892505aee57adf/colorama-0.3.9-py2.py3-none-any.whl
Collecting pythonnet==2.3.0 (from -r requirements.txt (line 2))
  Using cached https://files.pythonhosted.org/packages/89/3b/a22cd45b591d6cf490ee8b24d52b9db1f30b4b478b64a9b231c53474731e/pythonnet-2.3.0.tar.gz
Collecting pyinstaller==3.3.1 (from -r requirements.txt (line 3))
Collecting pefile>=2017.8.1 (from pyinstaller==3.3.1->-r requirements.txt (line 3))
Requirement already satisfied: setuptools in ./venv/lib/python3.5/site-packages (from pyinstaller==3.3.1->-r requirements.txt (line 3)) (41.0.1)
Collecting macholib>=1.8 (from pyinstaller==3.3.1->-r requirements.txt (line 3))
  Using cached https://files.pythonhosted.org/packages/41/f1/6d23e1c79d68e41eb592338d90a33af813f98f2b04458aaf0b86908da2d8/macholib-1.11-py2.py3-none-any.whl
Collecting future (from pefile>=2017.8.1->pyinstaller==3.3.1->-r requirements.txt (line 3))
Collecting altgraph>=0.15 (from macholib>=1.8->pyinstaller==3.3.1->-r requirements.txt (line 3))
  Using cached https://files.pythonhosted.org/packages/0a/cc/646187eac4b797069e2e6b736f14cdef85dbe405c9bfc7803ef36e4f62ef/altgraph-0.16.1-py2.py3-none-any.whl
Building wheels for collected packages: pythonnet
  Building wheel for pythonnet (setup.py) ... error
  ERROR: Complete output from command /home/jkirk/projects/misc/git-xltrail/venv/bin/python3 -u -c 'import setuptools, tokenize;__file__='"'"'/tmp/pip-install-jilzgp3v/pythonnet/setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' bdist_wheel -d /tmp/pip-wheel-vk_d05qc --python-tag cp35:
  ERROR: running bdist_wheel
  running build
  running build_ext
  Could not load file or assembly or one of its dependencies.
  Traceback (most recent call last):
    File "<string>", line 1, in <module>
    File "/tmp/pip-install-jilzgp3v/pythonnet/setup.py", line 405, in <module>
      zip_safe=False,
    File "/home/jkirk/projects/misc/git-xltrail/venv/lib/python3.5/site-packages/setuptools/__init__.py", line 145, in setup
      return distutils.core.setup(**attrs)
    File "/usr/lib/python3.5/distutils/core.py", line 148, in setup
      dist.run_commands()
    File "/usr/lib/python3.5/distutils/dist.py", line 955, in run_commands
      self.run_command(cmd)
    File "/usr/lib/python3.5/distutils/dist.py", line 974, in run_command
      cmd_obj.run()
    File "/home/jkirk/projects/misc/git-xltrail/venv/lib/python3.5/site-packages/wheel/bdist_wheel.py", line 192, in run
      self.run_command('build')
    File "/usr/lib/python3.5/distutils/cmd.py", line 313, in run_command
      self.distribution.run_command(command)
    File "/usr/lib/python3.5/distutils/dist.py", line 974, in run_command
      cmd_obj.run()
    File "/usr/lib/python3.5/distutils/command/build.py", line 135, in run
      self.run_command(cmd_name)
    File "/usr/lib/python3.5/distutils/cmd.py", line 313, in run_command
      self.distribution.run_command(command)
    File "/usr/lib/python3.5/distutils/dist.py", line 974, in run_command
      cmd_obj.run()
    File "/usr/lib/python3.5/distutils/command/build_ext.py", line 339, in run
      self.build_extensions()
    File "/usr/lib/python3.5/distutils/command/build_ext.py", line 448, in build_extensions
      self._build_extensions_serial()
    File "/usr/lib/python3.5/distutils/command/build_ext.py", line 473, in _build_extensions_serial
      self.build_extension(ext)
    File "/tmp/pip-install-jilzgp3v/pythonnet/setup.py", line 139, in build_extension
      self._install_packages()
    File "/tmp/pip-install-jilzgp3v/pythonnet/setup.py", line 269, in _install_packages
      subprocess.check_call(cmd, shell=use_shell)
    File "/usr/lib/python3.5/subprocess.py", line 271, in check_call
      raise CalledProcessError(retcode, cmd)
  subprocess.CalledProcessError: Command 'mono tools/nuget/nuget.exe update -self' returned non-zero exit status 1
  ----------------------------------------
  ERROR: Failed building wheel for pythonnet
  Running setup.py clean for pythonnet
Failed to build pythonnet
Installing collected packages: colorama, pythonnet, future, pefile, altgraph, macholib, pyinstaller
  Running setup.py install for pythonnet ... error
    ERROR: Complete output from command /home/jkirk/projects/misc/git-xltrail/venv/bin/python3 -u -c 'import setuptools, tokenize;__file__='"'"'/tmp/pip-install-jilzgp3v/pythonnet/setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' install --record /tmp/pip-record-v19pscej/install-record.txt --single-version-externally-managed --compile --install-headers /home/jkirk/projects/misc/git-xltrail/venv/include/site/python3.5/pythonnet:
    ERROR: running install
    running build
    running build_ext
    Could not load file or assembly or one of its dependencies.
    Traceback (most recent call last):
      File "<string>", line 1, in <module>
      File "/tmp/pip-install-jilzgp3v/pythonnet/setup.py", line 405, in <module>
        zip_safe=False,
      File "/home/jkirk/projects/misc/git-xltrail/venv/lib/python3.5/site-packages/setuptools/__init__.py", line 145, in setup
        return distutils.core.setup(**attrs)
      File "/usr/lib/python3.5/distutils/core.py", line 148, in setup
        dist.run_commands()
      File "/usr/lib/python3.5/distutils/dist.py", line 955, in run_commands
        self.run_command(cmd)
      File "/usr/lib/python3.5/distutils/dist.py", line 974, in run_command
        cmd_obj.run()
      File "/home/jkirk/projects/misc/git-xltrail/venv/lib/python3.5/site-packages/setuptools/command/install.py", line 61, in run
        return orig.install.run(self)
      File "/usr/lib/python3.5/distutils/command/install.py", line 583, in run
        self.run_command('build')
      File "/usr/lib/python3.5/distutils/cmd.py", line 313, in run_command
        self.distribution.run_command(command)
      File "/usr/lib/python3.5/distutils/dist.py", line 974, in run_command
        cmd_obj.run()
      File "/usr/lib/python3.5/distutils/command/build.py", line 135, in run
        self.run_command(cmd_name)
      File "/usr/lib/python3.5/distutils/cmd.py", line 313, in run_command
        self.distribution.run_command(command)
      File "/usr/lib/python3.5/distutils/dist.py", line 974, in run_command
        cmd_obj.run()
      File "/usr/lib/python3.5/distutils/command/build_ext.py", line 339, in run
        self.build_extensions()
      File "/usr/lib/python3.5/distutils/command/build_ext.py", line 448, in build_extensions
        self._build_extensions_serial()
      File "/usr/lib/python3.5/distutils/command/build_ext.py", line 473, in _build_extensions_serial
        self.build_extension(ext)
      File "/tmp/pip-install-jilzgp3v/pythonnet/setup.py", line 139, in build_extension
        self._install_packages()
      File "/tmp/pip-install-jilzgp3v/pythonnet/setup.py", line 269, in _install_packages
        subprocess.check_call(cmd, shell=use_shell)
      File "/usr/lib/python3.5/subprocess.py", line 271, in check_call
        raise CalledProcessError(retcode, cmd)
    subprocess.CalledProcessError: Command 'mono tools/nuget/nuget.exe update -self' returned non-zero exit status 1
    ----------------------------------------
ERROR: Command "/home/jkirk/projects/misc/git-xltrail/venv/bin/python3 -u -c 'import setuptools, tokenize;__file__='"'"'/tmp/pip-install-jilzgp3v/pythonnet/setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' install --record /tmp/pip-record-v19pscej/install-record.txt --single-version-externally-managed --compile --install-headers /home/jkirk/projects/misc/git-xltrail/venv/include/site/python3.5/pythonnet" failed with error code 1 in /tmp/pip-install-jilzgp3v/pythonnet/