Update requirements.txt

requirements.txt

@@ -10,6 +10,7 @@ PyPDF2
 imap_tools
 llama-index
 langchain-openai~=0.1.7
-langchain>=0.2.0,<0.3.0
-langchain-core>=0.2.0,<0.3.0
-langsmith>=0.1.17,<0.2.0
+langchain>=0.2.0
+langchain-core>=0.2.0
+langsmith>=0.1.17
+typing-extensions>=4.5.0