Update more docs with langchain integration (#65)

Update more docs with langchain integration.

README.md

@@ -16,9 +16,16 @@ output. You might even get results back.
 
 from kor.extraction import Extractor
 from kor.nodes import Object, Text
-from langchain.chat_models import ChatOpenAI
+from langchain import ChatOpenAI
+
+llm = ChatOpenAI(model_name="gpt-3.5-turbo", 
+    temperature = 0,
+    max_tokens = 2000,
+    frequency_penalty = 0,
+    presence_penalty = 0,
+    top_p = 1.0,
+)
 
-llm = ChatOpenAI(model_name="gpt-3.5-turbo")
 model = Extractor(llm)
 
 schema = Object(

docs/source/index.rst

@@ -18,11 +18,18 @@ Translate user input into structured JSON to use for an API **request**:
 
 .. code-block:: python
 
+  from langchain import ChatOpenAI
   from kor.extraction import Extractor
   from kor.nodes import Object, Text
-  from kor.llms import OpenAIChatCompletion
 
-  llm = OpenAIChatCompletion(model="gpt-3.5-turbo")
+  llm = ChatOpenAI(model_name="gpt-3.5-turbo", 
+      temperature = 0,
+      max_tokens = 2000,
+      frequency_penalty = 0,
+      presence_penalty = 0,
+      top_p = 1.0,
+  )
+
   model = Extractor(llm)
 
   schema = Object(