Update app.py

app.py

@@ -23,7 +23,7 @@ from langchain.indexes import VectorstoreIndexCreator
 from langchain.chains import RetrievalQA
 from langchain.evaluation.qa import QAEvalChain
 from langchain.prompts import StringPromptTemplate
-from langchain.tools.python.tool import PythonREPLTool
+# from langchain.tools.python.tool import PythonREPLTool
 from langchain.python import PythonREPL
 from langchain import LLMMathChain, SerpAPIWrapper, LLMChain
 from langchain.schema import AgentAction, AgentFinish, OutputParserException