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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 map_block_storage(service, pool, image):
 """Map a RADOS block device for local use."""

    cmd = [
        'rbd',
        'map',
        '{}/{}'.format(pool, image),
        '--user',
        service,
        '--secret',
        _keyfile_path(service),
    ]
    check_call(cmd)