def list(self):
        self.__ensure_index_filename()

        # With an index, distinct includes documents with no filename
        # as None.
        return [
            name for name in self.__files.distinct("filename")
            if name is not None]
List the names of all files stored in this instance of
dataset/ETHPy150Open blynch/CloudMemeBackend/gridfs/__init__.py/GridFS.list