copyfileobj doesn't support async file handles

[dj1471]

I was attempting to use copyfileobj but found that it doesn't support async file handles. This makes the function essentially useless as you wouldn't want to use a standard file handle in an async application.

Sample code:

#!/usr/bin/env python3
import asyncio
from aiopath import AsyncPath
import aioshutil


async def test():
    a = AsyncPath('a.txt').open()
    b = AsyncPath('b.txt').open()
    await aioshutil.copyfileobj(a, b)

asyncio.run(test())

Which returns:

Traceback (most recent call last):
File "/home/user/venv/./test.py", line 12, in
asyncio.run(test())
File "/usr/lib/python3.11/asyncio/runners.py", line 190, in run
return runner.run(main)
^^^^^^^^^^^^^^^^
File "/usr/lib/python3.11/asyncio/runners.py", line 118, in run
return self._loop.run_until_complete(task)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/lib/python3.11/asyncio/base_events.py", line 653, in run_until_complete
return future.result()
^^^^^^^^^^^^^^^
File "/home/user/venv/./test.py", line 10, in test
await aioshutil.copyfileobj(a, b)
File "/home/user/venv/lib/python3.11/site-packages/aioshutil/init.py", line 205, in run_in_executor
return await loop.run_in_executor(None, pfunc)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/lib/python3.11/concurrent/futures/thread.py", line 58, in run
result = self.fn(*self.args, **self.kwargs)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/lib/python3.11/shutil.py", line 194, in copyfileobj
fsrc_read = fsrc.read
^^^^^^^^^
AttributeError: '_AsyncGeneratorContextManager' object has no attribute 'read'