Generates a checkpoint for the partition using the curren offset and sequenceNumber for
        and persists to the checkpoint manager.

        :param event_processor_context An optional custom state value for the Event Processor.
         This data must be in a JSON serializable format.
        :type event_processor_context: str or dict

async def checkpoint_async(self, event_processor_context=None):
        """
        Generates a checkpoint for the partition using the curren offset and sequenceNumber for
        and persists to the checkpoint manager.

        :param event_processor_context An optional custom state value for the Event Processor.
         This data must be in a JSON serializable format.
        :type event_processor_context: str or dict
        """
        captured_checkpoint = Checkpoint(self.partition_id, self.offset, self.sequence_number)
        await self.persist_checkpoint_async(captured_checkpoint, event_processor_context)
        self.event_processor_context = event_processor_context