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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 parse_remote(cls, filename):
 """Parses a remote filename into bucket and key information. Handles S3 with optional region name specified in key: BUCKETNAME@REGIONNAME/KEY """

        parts = filename.split("//")[-1].split("/", 1)
        bucket, key = parts if len(parts) == 2 else (parts[0], None)
        if bucket.find("@") > 0:
            bucket, region = bucket.split("@")
        else:
            region = None

        return cls._REMOTE_FILE("s3", bucket, key, region)