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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 init_engine(self, get_loader):
 """ Construct and store a PipelineEngine from loader. If get_loader is None, constructs an ExplodingPipelineEngine """

        if get_loader is not None:
            self.engine = SimplePipelineEngine(
                get_loader,
                self.asset_finder,
                self.default_pipeline_domain(self.trading_calendar),
            )
        else:
            self.engine = ExplodingPipelineEngine()