Add support for async functions in memo library

Hi Vicent,

First, thank you for creating and maintaining the memo library. It has been incredibly useful for my projects. I am writing to request support for asynchronous functions in the memo library.

Here's an example of my use case:

import asyncio
from memo import memfile

@memfile("async_function.jsonl")
async def get_data():
    # Simulate some async work with asyncio.sleep
    await asyncio.sleep(1)
    return {"key1": "value1", "key2": "value2"}

# Example usage
async def main():
    result = await get_data()
    print(result)

# To run the example multiple times
if __name__ == "__main__":
    loop = asyncio.get_event_loop()
    for _ in range(5):
        loop.run_until_complete(main())

and the error:

Traceback (most recent call last):
  File "/home/hrobar/msd_projects/dssi-nlp-gracs-chatbot/other/async_code.py", line 20, in <module>
    loop.run_until_complete(main())
  File "/home/hrobar/miniconda3/envs/gracs-llm/lib/python3.11/asyncio/base_events.py", line 654, in run_until_complete
    return future.result()
           ^^^^^^^^^^^^^^^
  File "/home/hrobar/msd_projects/dssi-nlp-gracs-chatbot/other/async_code.py", line 13, in main
    result = await get_data()
                   ^^^^^^^^^^
  File "/home/hrobar/miniconda3/envs/gracs-llm/lib/python3.11/site-packages/memo/_base.py", line 108, in wrapper
    {**kwargs, **result},
    ^^^^^^^^^^^^^^^^^^^^
TypeError: 'coroutine' object is not a mapping
sys:1: RuntimeWarning: coroutine 'get_data' was never awaited
It appears that the memo library's decorator does not handle asynchronous functions properly, resulting in the TypeError: 'coroutine' object is not a mapping error.

I guess an additinal wrapper like this perhaps would be a way to go? (not sure how well it implements with yours code tho):

import asyncio
import orjson
import pathlib
from functools import wraps
from memo import memfile

def async_memfile(filepath: str, skip: bool = False):
    """
    Remembers input/output of an asynchronous function in a jsonl file on disk.

    Arguments:
        filepath: path to write data to
        skip: skips the calculation if kwargs appear in data already
    """

    def decorator(func):
        @wraps(func)
        async def wrapper(*args, **kwargs):
            result = await func(*args, **kwargs)
            if skip:
                if pathlib.Path(filepath).exists():
                    with open(filepath, "r") as f:
                        datalist = [orjson.loads(line) for line in list(f)]
                else:
                    datalist = []
            with open(filepath, "a") as f:
                if skip and _contains(kwargs, datalist):
                    return None
                ser = orjson.dumps(
                    {**kwargs, **result},
                    option=orjson.OPT_NAIVE_UTC | orjson.OPT_SERIALIZE_NUMPY,
                )
                f.write(ser.decode("utf-8") + "\n")
            return result

        return wrapper

    return decorator

Thank you for considering this feature request. I am looking forward to your response.

Best regards,

koaning / memo

Add support for async functions in memo library #43