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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 create_rbd_image(service, pool, image, sizemb):
 """Create a new RADOS block device."""

    cmd = ['rbd', 'create', image, '--size', str(sizemb), '--id', service,
           '--pool', pool]
    check_call(cmd)