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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 _build_meta(meta: str, pipelines: Iterable['Pipeline']) -> 'Pipeline': """Build a pipeline with a given meta-argument. :param meta: either union or intersection :param pipelines: """

        return Pipeline(protocol=[
            {
                'meta': meta,
                'pipelines': [
                    pipeline.protocol
                    for pipeline in pipelines
                ]
            },
        ])