community: Additional AWS deprecations (#29447)

Added deprecation warnings for a few more classes that weremoved to
`langchain-aws` package:
- [SageMaker Endpoint
LLM](https://python.langchain.com/api_reference/aws/retrievers/langchain_aws.retrievers.bedrock.AmazonKnowledgeBasesRetriever.html)
- [Amazon Kendra
retriever](https://python.langchain.com/api_reference/aws/retrievers/langchain_aws.retrievers.kendra.AmazonKendraRetriever.html)
- [Amazon Bedrock Knowledge Bases
retriever](https://python.langchain.com/api_reference/aws/retrievers/langchain_aws.retrievers.bedrock.AmazonKnowledgeBasesRetriever.html)

libs/community/langchain_community/llms/sagemaker_endpoint.py

@@ -5,6 +5,7 @@ import json
 from abc import abstractmethod
 from typing import Any, Dict, Generic, Iterator, List, Mapping, Optional, TypeVar, Union
 
+from langchain_core._api.deprecation import deprecated
 from langchain_core.callbacks import CallbackManagerForLLMRun
 from langchain_core.language_models.llms import LLM
 from langchain_core.utils import pre_init
@@ -124,6 +125,11 @@ class LLMContentHandler(ContentHandlerBase[str, str]):
     """Content handler for LLM class."""
 
 
+@deprecated(
+    since="0.3.16",
+    removal="1.0",
+    alternative_import="langchain_aws.llms.SagemakerEndpoint",
+)
 class SagemakerEndpoint(LLM):
     """Sagemaker Inference Endpoint models.
 

libs/community/langchain_community/retrievers/bedrock.py

@@ -1,5 +1,6 @@
 from typing import Any, Dict, List, Optional
 
+from langchain_core._api.deprecation import deprecated
 from langchain_core.callbacks import CallbackManagerForRetrieverRun
 from langchain_core.documents import Document
 from langchain_core.retrievers import BaseRetriever
@@ -18,6 +19,11 @@ class RetrievalConfig(BaseModel, extra="allow"):  # type: ignore[call-arg]
     vectorSearchConfiguration: VectorSearchConfig
 
 
+@deprecated(
+    since="0.3.16",
+    removal="1.0",
+    alternative_import="langchain_aws.AmazonKnowledgeBasesRetriever",
+)
 class AmazonKnowledgeBasesRetriever(BaseRetriever):
     """Amazon Bedrock Knowledge Bases retriever.
 

libs/community/langchain_community/retrievers/kendra.py

@@ -11,6 +11,7 @@ from typing import (
     Union,
 )
 
+from langchain_core._api.deprecation import deprecated
 from langchain_core.callbacks import CallbackManagerForRetrieverRun
 from langchain_core.documents import Document
 from langchain_core.retrievers import BaseRetriever
@@ -323,6 +324,11 @@ KENDRA_CONFIDENCE_MAPPING = {
 }
 
 
+@deprecated(
+    since="0.3.16",
+    removal="1.0",
+    alternative_import="langchain_aws.AmazonKendraRetriever",
+)
 class AmazonKendraRetriever(BaseRetriever):
     """`Amazon Kendra Index` retriever.