Replace deprecated @asyncio.coroutine with async/await

[uSpike]

asyncio.coroutine is deprecated since python 3.8 and will be removed in 3.10 (coming this year): https://docs.python.org/3/library/asyncio-task.html#asyncio.coroutine

Coroutine functions should be migrated to using async/await syntax, which would mean requiring python 3.5 or newer, which itself went EOL on 2017-08-08.

[swt2c]

It didn't end up getting removed in 3.10, but it has been removed in 3.11: https://bugs.python.org/issue43216

It would be good to get this fixed. :-)

[djuarezg]

May I presume the new fixed release could be published now that #764 and #752 have been done?

[StanHatko]

Could you please publish a release with this bug fixed, so that it works properly in Python 3.11? It seems the issues have been fixed in the code, only the new release that has these fixes needs to be published with a new version number.

[gsalvatella]

Please we should publish this. It's been years since the fix and even Debian had to patch pexpect because the fix hasn't been released. @takluyver @jquast

[dluyer]

Agreed: this is broken in Python 3.11 so we should release with the fix. Let's work out if there's anything else 'coming soon' or other reason to hold off on a release right now.

[StanHatko]

Could you please release the updated 4.9.0 version (which includes this bug fix) for conda as well (URLs: https://anaconda.org/anaconda/pexpect and https://anaconda.org/conda-forge/pexpect)? That way conda install pexpect will be for the updated version with this bug fixed.

[jquast]

Although I have permission to release to pypi, I don't believe that I have any permission to do anything about conda, I am not an anaconda package maintainer or contributor, there must be a better place to make the request to conda-forge to release their pexpect 4.8.0 package to 4.9.0?

[StanHatko]

The issue is fixed now in 4.9.0 (updated in conda-forge now as well conda-forge/pexpect-feedstock#29), so I think this issue can be closed.