Multiprocessing problems

[davide-grheco]

The library doesn't always work on all architectures when multiprocessing the fingerprints computations.
This should be fixed in #14 if I remember correctly.

In the meanwhile, I'll just point out that if anyone is having troubles with fingerprints computation, force the system to compute them on a single process and that should make it work - albeit a bit slower.
To do this, instantiate the model class and tell it not to perform multiprocessing for fingerprints.

ADMETModel(fingerprint_multiprocessing_min=number-larger-than-the-molecules-you-want-to-process)

I just remembered about this and figured it may be useful to someone.