from .model import InformationExtractedFromABillReceipt as PydanticModel from langchain.chains import LLMChain from langchain.chat_models import ChatOpenAI from langchain.output_parsers import PydanticOutputParser, OutputFixingParser from langchain.prompts import ( ChatPromptTemplate, HumanMessagePromptTemplate, SystemMessagePromptTemplate, ) model = ChatOpenAI( temperature=0, n=1, model_kwargs= { 'stop': None, 'top_p': 1, 'frequency_penalty': 0, 'presence_penalty': 0, } ) # Build categorizing chain system_message_prompt = SystemMessagePromptTemplate.from_template( "You are an information extraction engine that outputs details from OCR processed " "documents such as date/time/place of departure and arrival.\n" "{format_instructions}" ) human_message_prompt = HumanMessagePromptTemplate.from_template("{text}") chat_prompt = ChatPromptTemplate.from_messages( [system_message_prompt, human_message_prompt] ) output_parser = PydanticOutputParser(pydantic_object=PydanticModel) fixing_parser = OutputFixingParser.from_llm(llm=model, parser=output_parser) chain = LLMChain( llm=model, prompt=chat_prompt, output_parser=fixing_parser )