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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 get_unique_constraint_declaration_sql(self, name, index):
 """ Obtains DBMS specific SQL code portion needed to set a unique constraint declaration to be used in statements like CREATE TABLE. :param name: The name of the unique constraint. :type name: str :param index: The index definition :type index: Index :return: DBMS specific SQL code portion needed to set a constraint. :rtype: str """

        columns = index.get_quoted_columns(self)
        name = Identifier(name)

        if not columns:
            raise DBALException('Incomplete definition. "columns" required.')

        return "CONSTRAINT %s UNIQUE (%s)%s" % (
            name.get_quoted_name(self),
            self.get_index_field_declaration_list_sql(columns),
            self.get_partial_index_sql(index),
        )