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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 format(file_metrics, build_metrics):
 """compute output in JSON format."""

    metrics = {'files': file_metrics}
    if build_metrics:
        metrics['build'] = build_metrics
    body = json.dumps(metrics, sort_keys=True, indent=4) + '\n'
    return body