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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 close(self, *args, **kwargs):
 """ Engine closed, copy file to DB if it has changed """

        super(DatabaseWrapper, self).close(*args, **kwargs)

        signature_version = self.settings_dict.get("SIGNATURE_VERSION", "s3v4")
        s3 = boto3.resource(
            's3',
            config=botocore.client.Config(signature_version=signature_version),
        )

        try:
            with open(self.settings_dict['NAME'], 'rb') as f:
                fb = f.read()

                m = hashlib.md5()
                m.update(fb)
                if self.db_hash == m.hexdigest():
                    logging.debug("Database unchanged, not saving to remote DB!")
                    return

                bytesIO = BytesIO()
                bytesIO.write(fb)
                bytesIO.seek(0)

                s3_object = s3.Object(self.settings_dict['BUCKET'], self.settings_dict['REMOTE_NAME'])
                result = s3_object.put('rb', Body=bytesIO)
        except Exception as e:
            logging.debug(e)

        logging.debug("Saved to remote DB!")