`skmultilearn.dataset` missing `arff` dependency

[necrosource-bot]

Mirrored from scikit-multilearn/scikit-multilearn#301

Issue

In a notebook, when trying to use skmultilearn.dataset, running the code snippet

!pip3 install scikit-multilearn
import skmultilearn.dataset

throws the error that

----> 1 import arff
      2 import bz2
      3 import pickle
      4 from scipy import sparse
      5 import hashlib

ModuleNotFoundError: No module named 'arff'

Environment

Using Python 3.10.12 and scikit-multilearn 0.2.0 in a Colab notebook.

Workaround

Import arff (pip3 install arff).

Proposed Update

Add the arff dependency in setup.py.