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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 prepare_outputs(self, job):
 """ Called before job is started. If output is a `FileSystemTarget`, create parent directories so the hive command won't fail """

        outputs = flatten(job.output())
        for o in outputs:
            if isinstance(o, FileSystemTarget):
                parent_dir = os.path.dirname(o.path)
                if parent_dir and not o.fs.exists(parent_dir):
                    logger.info("Creating parent directory %r", parent_dir)
                    try:
                        # there is a possible race condition
                        # which needs to be handled here
                        o.fs.mkdir(parent_dir)
                    except FileAlreadyExists:
                        pass