Replace tagger.pickle with a JSON file.

[edong]

Replace tagger.pickle with a JSON file, tagger.json.

Benefits:

• JSON, being plain text, is more transparent and easier to inspect and review, and alleviates security concerns regarding unpickling data: https://docs.python.org/3/library/pickle.html https://www.benfrederickson.com/dont-pickle-your-data/

The tagger.json file was generated from tagger.pickle as follows:

 >>> import json
 >>> import pickle
 >>> x = pickle.load(open("tagger.pickle", "rb"))
 >>> json.dump(
 ...     {
 ...         'weights': x[0],
 ...         'tagdict': x[1],
 ...         'classes': sorted(list(x[2])),
 ...     },
 ...     open('tagger.json', 'w', encoding='utf-8'),
 ...     ensure_ascii=False, indent=2, sort_keys=True)

Running train_tagger.py at HEAD (commit 2e0fc06cee0e80fd8a89606016a1b66b848ac4c9) without changes already results in changes to tagger.pickle, so this pull request only converts tagger.pickle to tagger.json without generating a new model.

Running train_tagger.py with these changes produces a different model, but with the same JSON format present in the tagger.json in this pull request.

---

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[edong]

Thanks for the comments! I've reverted the documentation changes.

[jacksonllee]

Just added you to the acknowledgments section in the readme. Thanks again!