A Python cmd.Cmd shell for talking with Ollama model with context

ollama_shell.py

import ollama
import cmd

class OllamaShell(cmd.Cmd):
    """ A console to ask questions to any LLM supported by ollama """

    prompt = "ollama> "
    # Ollama service needs to be running locally
    def __init__(self, model='llama3.2:1b'):
        self.model = model
        # last line
        self.last = None
        # For context
        self.messages = [
            {
                "role": "system",
                "content": "You are a helpful, precise assistant."
            }
        ]
        print(f"Configured model is {model}")
        super().__init__()

    def do_last(self, arg):
        """ Print last asked question """
        if self.last:
            print(self.last)

    def do_reset(self, arg):
        """ Reset conversation context """
        # Keep system context
        self.messages = self.messages[:1]
        print("Reset conversation context.")

    def do_model(self, model):
        """ Change the model """

        model = model.strip()
        models = ollama.list()
        present = any(m.model == model for m in models["models"])
        if present:
            self.model = model
            print(f"Model set to {model}.")
        else:
            print(f"error - model {model} not available in ollama.")
    
    def emptyline(self):
        """ Override this otherwise previous lines are repeated in the prompt """
        return
    
    def default(self, line: str):
        """
        Called when the input line does not match a known command.
        We interpret the entire line as a prompt for the LLM.
        """
        line = line.strip()
        
        try:
            message = {"role": "user", "content": line}
            self.messages.append(message)
            
            response = ollama.chat(
                model=self.model,
                messages = self.messages
            )

            model_response = msg = response["message"]["content"]
            self.messages.append(
                {"role": "assistant", "content": model_response}
            )
            print(model_response)
            self.last = line
        except Exception as exc:
            print(f"[error] {exc}")
    
    def do_EOF(self, arg):
        print("Goodbye.")
        return True

Referring bug in CPython - python/cpython#143804