emmet-core requirement for openbabel not declared

[drew-parsons]

emmet-core uses openbabel (in emmet.core.qchem.molecule), but the dependency is not declared in setup.py. This makes packaging and installing more complex than it needs to be. Looks like openbabel should be added to the install_requires list in the setup.py for emmet-core.

[Andrew-S-Rosen]

@drew-parsons: Thanks for raising this issue. I agree that this would be very nice to add. Unfortunately, we are limited by the fact that pip is not working with the current version of openbabel (see openbabel/openbabel#2571). Until that issue is resolved or a new PyPI release is made, there's unfortunately not much that can be done in terms of the setup.py.

CC'ing @munrojm.

[tschaume]

Adding openbabel-wheel as a dependency might be an option despite being an unofficial repo (see later comment in the issue that @Andrew-S-Rosen linked).

[drew-parsons]

You can use an Ubuntu or Debian installation, with openbabel installed by the deb packages (python3-openbabel, libopenbabel-dev, openbabel). If your usual workstation uses a Microsoft Windows operating system instead of Linux, you can install a Linux (Ubuntu) environment via Microsoft's WSL.