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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 get_bootstrap_osd_key(cluster):
 """ Read the bootstrap-osd key for `cluster`. """

    path = '{cluster}.bootstrap-osd.keyring'.format(cluster=cluster)
    try:
        with open(path, 'rb') as f:
            return f.read()
    except IOError:
        raise RuntimeError('bootstrap-osd keyring not found; run \'gatherkeys\'')