"six" is missing from the installation requirements

[PatWalters]

"pip install ." failed. I was able to fix this with "pip install six".

  Preparing metadata (setup.py) ... error
  error: subprocess-exited-with-error

  × python setup.py egg_info did not run successfully.
  │ exit code: 1
  ╰─> [8 lines of output]
      Traceback (most recent call last):
        File "", line 2, in 
        File "", line 34, in 
        File "/tmp/pip-install-idfp_634/oddt_b07b587cfb8d43389fcfd169d9bf418a/setup.py", line 3, in 
          from oddt import __version__ as VERSION
        File "/tmp/pip-install-idfp_634/oddt_b07b587cfb8d43389fcfd169d9bf418a/oddt/__init__.py", line 17, in 
          import six
      ModuleNotFoundError: No module named 'six'
      [end of output]

[naefl]

thanks for the report @PatWalters, for posterity - we're currently working on slimming down some of the dependencies and breaking it down into subpackages to work around openstructure install hassles