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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 generate_query_batches( self, sql, params=None, param_types=None, partition_size_bytes=None, max_partitions=None, ):
 """Start a partitioned query operation. Uses the ``PartitionQuery`` API request to start a partitioned query operation. Returns a list of batch information needed to peform the actual queries. :type sql: str :param sql: SQL query statement :type params: dict, {str -> column value} :param params: values for parameter replacement. Keys must match the names used in ``sql``. :type param_types: dict[str -> Union[dict, .types.Type]] :param param_types: (Optional) maps explicit types for one or more param values; required if parameters are passed. :type partition_size_bytes: int :param partition_size_bytes: (Optional) desired size for each partition generated. The service uses this as a hint, the actual partition size may differ. :type partition_size_bytes: int :param partition_size_bytes: (Optional) desired size for each partition generated. The service uses this as a hint, the actual partition size may differ. :type max_partitions: int :param max_partitions: (Optional) desired maximum number of partitions generated. The service uses this as a hint, the actual number of partitions may differ. :rtype: iterable of dict :returns: mappings of information used peform actual partitioned reads via :meth:`process_read_batch`. """

        partitions = self._get_snapshot().partition_query(
            sql=sql,
            params=params,
            param_types=param_types,
            partition_size_bytes=partition_size_bytes,
            max_partitions=max_partitions,
        )

        query_info = {"sql": sql}
        if params:
            query_info["params"] = params
            query_info["param_types"] = param_types

        for partition in partitions:
            yield {"partition": partition, "query": query_info}