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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 init_group(self, group, chunk_size, compression=None, compression_opts=None):
 """Initializes a HDF5 group compliant with the stored data. This method creates the datasets 'items', 'labels', 'features' and 'index' and leaves them empty. :param h5py.Group group: The group to initializes. :param float chunk_size: The size of a chunk in the file (in MB). :param str compression: Optional compression, see :class:`h5features.writer` for details :param str compression: Optional compression options, see :class:`h5features.writer` for details """

        create_index(group, chunk_size)

        self._entries['items'].create_dataset(
            group, chunk_size, compression=compression,
            compression_opts=compression_opts)

        self._entries['features'].create_dataset(
            group, chunk_size, compression=compression,
            compression_opts=compression_opts)

        # chunking the labels depends on features chunks
        self._entries['labels'].create_dataset(
            group, self._entries['features'].nb_per_chunk,
            compression=compression,
            compression_opts=compression_opts)

        if self.has_properties():
            self._entries['properties'].create_dataset(
                group, compression=compression,
                compression_opts=compression_opts)