Running async code on demand from @property

import asyncio

class A:
    def __init__(self):
        self.mylist = []

    @property
    def show_list(self):
        if not self.mylist:
            asyncio.run(self.load_list())  # neither works?
            asyncio.create_task(self.load_list())
        return self.mylist

    async def load_list(self):
        await asyncio.sleep(1)
        self.mylist = [1]


async def test():
    f = A()
    print(f.show_list)


asyncio.run(test())

I am trying to run a code like this, the main feature being show_list is a property of A, and contains some data to be loaded only when required. However, when running the snippet above, I get these errors:

RuntimeError: asyncio.run() cannot be called from a running event loop
sys:1: RuntimeWarning: coroutine 'A.load_list' was never awaited

How can I keep the property while loading the data on demand?