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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_xgboost_json(model):
 """ This gets a JSON dump of an XGBoost model while ensuring the features names are their indexes. """

    fnames = model.feature_names
    model.feature_names = None
    json_trees = model.get_dump(with_stats=True, dump_format="json")
    model.feature_names = fnames

    # this fixes a bug where XGBoost can return invalid JSON
    json_trees = [t.replace(": inf,", ": 1000000000000.0,") for t in json_trees]
    json_trees = [t.replace(": -inf,", ": -1000000000000.0,") for t in json_trees]

    return json_trees