async def list_time_slots_async(
        self, project_id: str, processor_id: str, filter_str: str = ''
    ) -> list[quantum.QuantumTimeSlot]:
        """Returns a list of quantum time slots on a processor.

        Args:
            project_id: A project_id of the parent Google Cloud Project.
            processor_id: The processor unique identifier.
            filter_str:  A string expression for filtering the quantum
                time slots returned by the list command. The fields
                eligible for filtering are `start_time`, `end_time`.

        Returns:
            A list of QuantumTimeSlot objects.
        """
        request = quantum.ListQuantumTimeSlotsRequest(
            parent=_processor_name_from_ids(project_id, processor_id), filter=filter_str
        )
        return await self._send_list_request_async(
            self.grpc_client.list_quantum_time_slots, request
        )
Returns a list of quantum time slots on a processor.

        Args:
            project_id: A project_id of the parent Google Cloud Project.
            processor_id: The processor unique identifier.
            filter_str:  A string expression for filtering the quantum
                time slots returned by the list command. The fields
                eligible for filtering are `start_time`, `end_time`.

        Returns:
            A list of QuantumTimeSlot objects.
        
cirq-google/cirq_google/engine/engine_client.py