https://github.com/googleapis/google-cloud-python/blob/a5af6acb85d8e1ed97e56ad7fc1cb0aefc524e61/pubsub/google/cloud/pubsub_v1/publisher/client.py#L166 Publish retry is supported in [Node.js](https://cloud.google.com/nodejs/docs/reference/pubsub/0.20.x/v1.PublisherClient#publish) and [Java](https://github.com/googleapis/google-cloud-java/blob/eb9fae59a236773a38c87dbce82206d4a267bf76/google-cloud-examples/src/main/java/com/google/cloud/examples/pubsub/snippets/PublisherSnippets.java#L107). It should be supported by Python too.