[BUG] Cannot use load_flow in AzureML prompt flow about promptflow HOT 1 OPEN

from promptflow import load_flow, tool
from promptflow.connections import AzureOpenAIConnection

from jinja2 import Template
from promptflow.tools.aoai import chat

# The inputs section will change based on the arguments of the tool function, after you save the code
# Adding type to arguments and return value will help the system show the types properly
# Please update the function name/signature per need

# In Python tool you can do things like calling external services or
# pre/post processing of data, pretty much anything you want


@tool
def echo(input: str, my_connection: AzureOpenAIConnection) -> str:
    # subjoke = load_flow("./subjoke")
    # print(subjoke.context)
    # print(subjoke.context.connections)
    # subjoke_output = subjoke(topic=input, connection=my_connection)

    # instead of load sub flow as a flow, directly call tools here
    # load prompt
    with open("subjoke/joke.jinja2", "r", encoding="utf-8") as f:
        tmpl = Template(f.read(), trim_blocks=True, keep_trailing_newline=True)
        prompt = tmpl.render(topic=input)
    
    # directly call tool function with connection object
    output = chat(
        connection=my_connection,
        prompt=prompt,
        deployment_name="gpt-35-turbo",
        max_tokens=256,
        temperature=0.7,
    )
    return output