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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 _sanitize_entity(self, entity):
 """ Make given entity 'sane' for further use. """

        aliases = {
            "current_state": "state",
            "is_flapping": "flapping",
            "scheduled_downtime_depth": "in_downtime",
            "has_been_checked": "checked",
            "should_be_scheduled": "scheduled",
            "active_checks_enabled": "active_checks",
            "passive_checks_enabled": "passive_checks",
        }
        sane = {}
        for akey in aliases.keys():
            sane[aliases[akey]] = None

        aliases_keys = aliases.keys()
        for key in entity.keys():
            if key not in aliases_keys:
                continue

            alias = aliases[key]
            try:
                sane[alias] = int(entity[key])
            except Exception:
                sane[alias] = None

        if sane["active_checks"] not in [0, 1]:
            sane["active_checks"] = 0
        elif sane["active_checks"] == 1:
            sane["passive_checks"] = 0

        if sane["passive_checks"] not in [0, 1]:
            sane["passive_checks"] = 0

        return sane