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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 manage_initial_host_status_brok(self, b):
 """Prepare the known hosts cache"""

        host_name = b.data['host_name']
        logger.debug("got initial host status: %s", host_name)

        self.hosts_cache[host_name] = {
            'realm_name':
                sanitize_name(b.data.get('realm_name', b.data.get('realm', 'All'))),
        }
        if 'customs' in b.data:
            self.hosts_cache[host_name]['_GRAPHITE_PRE'] = \
                sanitize_name(b.data['customs'].get('_GRAPHITE_PRE', None))
            self.hosts_cache[host_name]['_GRAPHITE_GROUP'] = \
                sanitize_name(b.data['customs'].get('_GRAPHITE_GROUP', None))
        logger.debug("initial host status received: %s", host_name)