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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 to_sql(self, instring, schema, use_bag_semantics=False):
 """ Translate a relational algebra string into a SQL string. :param instring: a relational algebra string to translate :param schema: a mapping of relation names to their attributes :param use_bag_semantics: flag for using relational algebra bag semantics :return: a SQL translation string """

        root_list = self.to_syntax_tree(instring, schema)
        return sql_translator.translate(root_list, use_bag_semantics)