Python: Restore Titan model example. (#7621)

Author: rlhagerm

.doc_gen/metadata/bedrock-runtime_metadata.yaml

@@ -1483,3 +1483,20 @@ bedrock-runtime_Scenario_GenerateVideos_NovaReel:
                 - bedrock-runtime.java2.NovaReel.VideoGeneration
   services:
     bedrock-runtime: {StartAsyncInvoke, GetAsyncInvoke}
+
+bedrock-runtime_InvokeModel_TitanText:
+  title: Invoke Amazon Titan Text models on &BR; using the Invoke Model API
+  title_abbrev: "InvokeModel"
+  synopsis: send a text message to Amazon Titan Text, using the Invoke Model API.
+  category: Amazon Titan Text
+  languages:
+    Python:
+      versions:
+        - sdk_version: 3
+          github: python/example_code/bedrock-runtime
+          excerpts:
+            - description: Use the Invoke Model API to send a text message.
+              snippet_tags:
+                - python.example_code.bedrock-runtime.InvokeModel_TitanText
+  services:
+    bedrock-runtime: {InvokeModel}

python/example_code/bedrock-runtime/README.md

@@ -64,6 +64,10 @@ functions within the same service.
 
 - [InvokeModel](models/amazon_titan_image_generator/invoke_model.py#L4)
 
+### Amazon Titan Text
+
+- [InvokeModel](models/amazon_titan_text/invoke_model.py#L4)
+
 ### Amazon Titan Text Embeddings
 
 - [InvokeModel](models/amazon_titan_text_embeddings/invoke_model.py#L4)

python/example_code/bedrock-runtime/models/amazon_titan_text/invoke_model.py

@@ -0,0 +1,48 @@
+# Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+# SPDX-License-Identifier: Apache-2.0
+
+# snippet-start:[python.example_code.bedrock-runtime.InvokeModel_TitanText]
+# Use the native inference API to send a text message to Amazon Titan Text.
+
+import boto3
+import json
+
+from botocore.exceptions import ClientError
+
+# Create a Bedrock Runtime client in the AWS Region of your choice.
+client = boto3.client("bedrock-runtime", region_name="us-east-1")
+
+# Set the model ID, e.g., Titan Text Premier.
+model_id = "amazon.titan-text-premier-v1:0"
+
+# Define the prompt for the model.
+prompt = "Describe the purpose of a 'hello world' program in one line."
+
+# Format the request payload using the model's native structure.
+native_request = {
+    "inputText": prompt,
+    "textGenerationConfig": {
+        "maxTokenCount": 512,
+        "temperature": 0.5,
+    },
+}
+
+# Convert the native request to JSON.
+request = json.dumps(native_request)
+
+try:
+    # Invoke the model with the request.
+    response = client.invoke_model(modelId=model_id, body=request)
+
+except (ClientError, Exception) as e:
+    print(f"ERROR: Can't invoke '{model_id}'. Reason: {e}")
+    exit(1)
+
+# Decode the response body.
+model_response = json.loads(response["body"].read())
+
+# Extract and print the response text.
+response_text = model_response["results"][0]["outputText"]
+print(response_text)
+
+# snippet-end:[python.example_code.bedrock-runtime.InvokeModel_TitanText]