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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 dataset_download_files(self, dataset, path=None, force=False, quiet=True, unzip=False):
 """ download all files for a dataset Parameters ========== dataset: the string identified of the dataset should be in format [owner]/[dataset-name] path: the path to download the dataset to force: force the download if the file already exists (default False) quiet: suppress verbose output (default is True) unzip: if True, unzip files upon download (default is False) """

        if dataset is None:
            raise ValueError('A dataset must be specified')
        if '/' in dataset:
            self.validate_dataset_string(dataset)
            dataset_urls = dataset.split('/')
            owner_slug = dataset_urls[0]
            dataset_slug = dataset_urls[1]
        else:
            owner_slug = self.get_config_value(self.CONFIG_NAME_USER)
            dataset_slug = dataset

        if path is None:
            effective_path = self.get_default_download_dir(
                'datasets', owner_slug, dataset_slug)
        else:
            effective_path = path

        response = self.process_response(
            self.datasets_download_with_http_info(
                owner_slug=owner_slug,
                dataset_slug=dataset_slug,
                _preload_content=False))

        outfile = os.path.join(effective_path, dataset_slug + '.zip')
        if force or self.download_needed(response, outfile, quiet):
            self.download_file(response, outfile, quiet)
            downloaded = True
        else:
            downloaded = False

        if downloaded:
            outfile = os.path.join(effective_path, dataset_slug + '.zip')
            if unzip:
                try:
                    with zipfile.ZipFile(outfile) as z:
                        z.extractall(effective_path)
                except zipfile.BadZipFile as e:
                    raise ValueError(
                        'Bad zip file, please report on '
                        'www.github.com/kaggle/kaggle-api', e)

                try:
                    os.remove(outfile)
                except OSError as e:
                    print('Could not delete zip file, got %s' % e)