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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 exists(self, filename):
 """Determines whether a path exists or not."""

        client = boto3.client("s3")
        bucket, path = self.bucket_and_path(filename)
        r = client.list_objects(Bucket=bucket, Prefix=path, Delimiter="/")
        if r.get("Contents") or r.get("CommonPrefixes"):
            return True
        return False