Adding App

.env-sample

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+ANTHROPIC_API_KEY=""

app.py

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+from langchain.chat_models import ChatAnthropic
+from langchain import PromptTemplate, LLMChain
+from langchain.prompts.chat import (
+    ChatPromptTemplate,
+    SystemMessagePromptTemplate,
+    AIMessagePromptTemplate,
+    HumanMessagePromptTemplate,
+)
+from langchain.schema import AIMessage, HumanMessage, SystemMessage
+import streamlit as st
+from dotenv import load_dotenv
+import PyPDF2
+
+load_dotenv()
+
+
+class LegalExpert:
+    def __init__(self):
+        self.system_prompt = self.get_system_prompt()
+
+        self.user_prompt = HumanMessagePromptTemplate.from_template("{legal_question}")
+
+        full_prompt_template = ChatPromptTemplate.from_messages(
+            [self.system_prompt, self.user_prompt]
+        )
+
+        self.chat = ChatAnthropic()
+
+        self.chain = LLMChain(llm=self.chat, prompt=full_prompt_template)
+
+    def get_system_prompt(self):
+        system_prompt = """
+        You are a Canadian Legal Expert. 
+
+        Under no circumstances do you give legal advice.
+        
+        You are adept at explaining the law in laymans terms, and you are able to provide context to legal questions.
+
+        While you can add context outside of the provided context, please do not add any information that is not directly relevant to the question, or the provided context.
+
+        You speak {language}.
+
+        ### CONTEXT
+        {context}
+
+        ### END OF CONTEXT
+        """
+
+        return SystemMessagePromptTemplate.from_template(system_prompt)
+
+    def run_chain(self, language, context, question):
+        return self.chain.run(
+            language=language, context=context, legal_question=question
+        )
+
+
+def retrieve_pdf_text(pdf_file):
+    pdf_reader = PyPDF2.PdfReader(pdf_file)
+    text = ""
+    for page in pdf_reader.pages:
+        text += page.extract_text()
+    return text
+
+
+# create a streamlit app
+st.title("Canadian Legal Explainer (that does not give advice)")
+
+if "LegalExpert" not in st.session_state:
+    st.session_state.LegalExpert = LegalExpert()
+
+# create a upload file widget for a pdf
+pdf_file = st.file_uploader("Upload a PDF file", type=["pdf"])
+
+# if a pdf file is uploaded
+if pdf_file:
+    # retrieve the text from the pdf
+    if "context" not in st.session_state:
+        st.session_state.context = retrieve_pdf_text(pdf_file)
+
+# create a button that clears the context
+if st.button("Clear context"):
+    st.session_state.__delitem__("context")
+    st.session_state.__delitem__("legal_response")
+
+# if there's context, proceed
+if "context" in st.session_state:
+    # create a dropdown widget for the language
+    language = st.selectbox("Language", ["English", "Français"])
+    # create a text input widget for a question
+    question = st.text_input("Ask a question")
+
+    # create a button to run the model
+    if st.button("Run"):
+        # run the model
+        legal_response = st.session_state.LegalExpert.run_chain(
+            language=language, context=st.session_state.context, question=question
+        )
+
+        if "legal_response" not in st.session_state:
+            st.session_state.legal_response = legal_response
+
+        else:
+            st.session_state.legal_response = legal_response
+
+# display the response
+if "legal_response" in st.session_state:
+    st.write(st.session_state.legal_response)

requirements.txt

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+streamlit
+langchain
+openai
+python-dotenv