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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 version(self):
 """What's the version of this database? Found in metadata attached by datacache when creating this database."""

        query = "SELECT version FROM %s" % METADATA_TABLE_NAME
        cursor = self.connection.execute(query)
        version = cursor.fetchone()
        if not version:
            return 0
        else:
            return int(version[0])