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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 delete_series(self, database=None, measurement=None, tags=None):
 """Delete series from a database. Series must be filtered by either measurement and tags. This method cannot be used to delete all series, use `drop_database` instead. :param database: the database from which the series should be deleted, defaults to client's current database :type database: str :param measurement: Delete all series from a measurement :type measurement: str :param tags: Delete all series that match given tags :type tags: dict """

        database = database or self._database
        query_str = 'DROP SERIES'
        if measurement:
            query_str += ' FROM {0}'.format(quote_ident(measurement))

        if tags:
            tag_eq_list = ["{0}={1}".format(quote_ident(k), quote_literal(v))
                           for k, v in tags.items()]
            query_str += ' WHERE ' + ' AND '.join(tag_eq_list)
        self.query(query_str, database=database, method="POST")