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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 _set_cdn_defaults(self):
 """Sets all the CDN-related attributes to default values."""

        if self._cdn_enabled is FAULT:
            self._cdn_enabled = False
        self._cdn_uri = None
        self._cdn_ttl = DEFAULT_CDN_TTL
        self._cdn_ssl_uri = None
        self._cdn_streaming_uri = None
        self._cdn_ios_uri = None
        self._cdn_log_retention = False