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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_coordinates_for_dataset_keys(self, dsids):
 """Get all coordinates."""

        coordinates = {}
        for dsid in dsids:
            cids = self._get_coordinates_for_dataset_key(dsid)
            coordinates.setdefault(dsid, []).extend(cids)
        return coordinates