Add helpful error message

[chasemc]

Autometa/autometa/validation/datasets.py

Line 47 in baf61c0

raise NotImplementedError

Currently the error has to be traced back to the code:

Traceback (most recent call last):
  File "/home/chase/miniconda3/envs/autometa/bin/autometa-download-dataset", line 8, in <module>
    sys.exit(main())
  File "/home/chase/miniconda3/envs/autometa/lib/python3.10/site-packages/autometa/validation/datasets.py", line 197, in main
    download(
  File "/home/chase/miniconda3/envs/autometa/lib/python3.10/site-packages/autometa/validation/datasets.py", line 47, in download
    raise NotImplementedError
NotImplementedError

[chasemc]

Example of how to do so:

Autometa/autometa/common/utilities.py

Line 211 in 52fd5b0

raise KeyError(f"member not in tarchive : {member} : {tarchive}")