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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 export(self, container, chunk_size=DEFAULT_DATA_CHUNK_SIZE):
 """ Export the contents of a filesystem as a tar archive. Args: container (str):
 The container to export chunk_size (int):
 The number of bytes returned by each iteration of the generator. If ``None``, data will be streamed as it is received. Default: 2 MB Returns: (generator):
 The archived filesystem data stream Raises: :py:class:`docker.errors.APIError` If the server returns an error. """

        res = self._get(
            self._url("/containers/{0}/export", container), stream=True
        )
        return self._stream_raw_result(res, chunk_size, False)