def _download_and_prepare(self, dl_manager):
        import nltk

        nltk.download("wordnet")
        if NLTK_VERSION >= version.Version("3.6.5"):
            nltk.download("punkt")
        if NLTK_VERSION >= version.Version("3.6.6"):
            nltk.download("omw-1.4")
    def _compute(self, predictions, references, alpha=0.9, beta=3, gamma=0.5):
        if NLTK_VERSION >= version.Version("3.6.5"):
            scores = [
                meteor_score.single_meteor_score(word_tokenize(ref),
                                                 word_tokenize(pred),
                                                 alpha=alpha,
                                                 beta=beta,
                                                 gamma=gamma)
                for ref, pred in zip(references, predictions)
            ]
        else:
            scores = [
                meteor_score.single_meteor_score(ref,
                                                 pred,
                                                 alpha=alpha,
                                                 beta=beta,
                                                 gamma=gamma)
                for ref, pred in zip(references, predictions)
            ]

        return {"meteor": np.mean(scores)}
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
""" METEOR metric. """

import numpy as np
from nltk.translate import meteor_score

import datasets
from datasets.config import importlib_metadata, version

NLTK_VERSION = version.parse(importlib_metadata.version("nltk"))
if NLTK_VERSION >= version.Version("3.6.4"):
    from nltk import word_tokenize

_CITATION = """\
@inproceedings{banarjee2005,
  title     = {{METEOR}: An Automatic Metric for {MT} Evaluation with Improved Correlation with Human Judgments},
  author    = {Banerjee, Satanjeev  and Lavie, Alon},
  booktitle = {Proceedings of the {ACL} Workshop on Intrinsic and Extrinsic Evaluation Measures for Machine Translation and/or Summarization},
  month     = jun,
  year      = {2005},
  address   = {Ann Arbor, Michigan},
  publisher = {Association for Computational Linguistics},
  url       = {https://www.aclweb.org/anthology/W05-0909},
  pages     = {65--72},
}
"""