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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_per_data_dir(self, dir_base, subpath):
 """Extend the given base directory with a per-data component. The method creates a private path for the :class:`~resolwe.flow.models.Data` object, such as:: ./test_data/1/ if ``base_dir`` is ``'./test_data'`` and ``subpath`` is ``1``. :param dir_base: The base path to be extended. This will usually be one of the directories configured in the ``FLOW_EXECUTOR`` setting. :param subpath: Objects's subpath used for the extending. :return: The new path for the :class:`~resolwe.flow.models.Data` object. :rtype: str """

        # Use Django settings here, because the state must be preserved
        # across events. This also implies the directory settings can't
        # be patched outside the manager and then just sent along in the
        # command packets.
        result = self.settings_actual.get('FLOW_EXECUTOR', {}).get(dir_base, '')
        return os.path.join(result, subpath)