What differences are there between ChatGPT and Instructional GPT?
Both ChatGPT and InstructGPT are auto-regressive large language models trained and made available by OpenAI. They are sibling models in the GPT-3.5 family and have been pretrained on natural language and code. They have also both been fine-tuned on human instructions and feedback.

The ChatGPT model and interface is optimized for use as a dialog agent by human users. It is available for free on a somewhat limited basis or can be purchased for a monthly fee. It has been trained specifically as a dialog agent and has enhanced safety measures to allow it to be exposed directly to end users.

The InstructGPT model is similar, but not identical, to the model that powers ChatGPT. It is not as restrictive as the ChatGPT model in terms of safety. It is not easily accessible to the public and is instead made available as a paid API. Requests to InstructGPT are billed based on the number of tokens returned, whereas ChatGPT is billed at a fixed monthly price regardless of usage.

Overall, these are very similar models that can be used for similar purposes, but ChatGPT is best suited for dialog with end users, while InstructGPT is useful for developers integrating API calls to a large language model into other applications.
Can you provide me some sample code to access the InstructGPT API in python?
Sure. Here is some sample code in Python to access the InstructGPT API:

import requests

# Set up the parameters
params = {
    model: instructgpt,
    prompt: What is the weather like in Seattle today?,
    max_tokens: 100
}

# Make the request
response = requests.post(https://api.openai.com/v1/engines/instructgpt/completions, json=params)

# Check the response
if response.status_code == 200:
    # Get the response text
    response_text = response.json()[choices][0][text]
    print(response_text)
else:
    print(Error: {}.format(response.text))