feat(batch prediction): Adds tuned model support comments to samples. (#13392)

* Adds tuned model support comments to samples.

* changes gemini model in samples to 2.5 flash

* changes gemini model in samples to 2.5 flash

Author: br1mendez

genai/batch_prediction/batchpredict_with_bq.py

@@ -26,6 +26,8 @@ def generate_content(output_uri: str) -> str:
     # output_uri = f"bq://your-project.your_dataset.your_table"
 
     job = client.batches.create(
+        # To use a tuned model, set the model param to your tuned model using the following format:
+        # model="projects/{PROJECT_ID}/locations/{LOCATION}/models/{MODEL_ID}
         model="gemini-2.0-flash-001",
         src="bq://storage-samples.generative_ai.batch_requests_for_multimodal_input",
         config=CreateBatchJobConfig(dest=output_uri),

genai/batch_prediction/batchpredict_with_gcs.py

@@ -26,6 +26,8 @@ def generate_content(output_uri: str) -> str:
 
     # See the documentation: https://googleapis.github.io/python-genai/genai.html#genai.batches.Batches.create
     job = client.batches.create(
+        # To use a tuned model, set the model param to your tuned model using the following format:
+        # model="projects/{PROJECT_ID}/locations/{LOCATION}/models/{MODEL_ID}
         model="gemini-2.0-flash-001",
         # Source link: https://storage.cloud.google.com/cloud-samples-data/batch/prompt_for_batch_gemini_predict.jsonl
         src="gs://cloud-samples-data/batch/prompt_for_batch_gemini_predict.jsonl",