fix: Ollama import statements (#15493)

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docs/docs/integrations/providers/ollama.mdx

@@ -21,7 +21,7 @@ To use, you should set up the environment variables `ANYSCALE_API_BASE` and
 ## LLM
 
 ```python
-from langchain_community.llms import Ollama
+from langchain.llms import Ollama
 ```
 
 See the notebook example [here](/docs/integrations/llms/ollama).
@@ -31,7 +31,7 @@ See the notebook example [here](/docs/integrations/llms/ollama).
 ### Chat Ollama
 
 ```python
-from langchain_community.chat_models import ChatOllama
+from langchain.chat_models import ChatOllama
 ```
 
 See the notebook example [here](/docs/integrations/chat/ollama).
@@ -47,7 +47,7 @@ See the notebook example [here](/docs/integrations/chat/ollama_functions).
 ## Embedding models
 
 ```python
-from langchain_community.embeddings import OllamaEmbeddings
+from langchain.embeddings import OllamaEmbeddings
 ```
 
 See the notebook example [here](/docs/integrations/text_embedding/ollama).