Langchain Vertex AI

Python package: google-cloud-aiplatform
Environment setup:
    Credentials (gcloud, workload identity)
    Or GOOGLE_APPLICATION_CREDENTIALS environment variable

Install Command:

pip install langchain google-cloud-aiplatform

Documentation:

Application Default Credentials

Google Auth Library

Code 1

from langchain.llms import VertexAI
llm = VertexAI()
print(llm("What are some of the pros and cons of Python as a programming language?"))

Code 2

from langchain.prompts import PromptTemplate
template = "Question: {question}\nAnswer: Let's think step by step."
prompt = PromptTemplate.from_template(template)
chain = prompt | llm
question = "Who was the president in the year Justin Beiber was born?"
print(chain.invoke({"question": question}))

Code 3

llm = VertexAI(model_name="code-bison", max_output_tokens=1000, temperature=0.3)
question = "Write a python function that checks if a string is a valid email address"
print(llm(question))

Code 4

result = llm.generate([question])
result.generations

Code 5

import asyncio
asyncio.run(llm.agenerate([question]))

Code 6

import sys
for chunk in llm.stream(question):
sys.stdout.write(chunk)
sys.stdout.flush()