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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_ceph_df(self, sentry_unit):
 """Return dict of ceph df json output, including ceph pool state. :param sentry_unit: Pointer to amulet sentry instance (juju unit) :returns: Dict of ceph df output """

        cmd = 'sudo ceph df --format=json'
        output, code = sentry_unit.run(cmd)
        if code != 0:
            msg = ('{} `{}` returned {} '
                   '{}'.format(sentry_unit.info['unit_name'],
                               cmd, code, output))
            amulet.raise_status(amulet.FAIL, msg=msg)
        return json.loads(output)