fix proxy usage for python-asyncio, fixes #9995

[ntextreme3]

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Description of the PR

This fixes #9995. From what I can tell, the proxy usage in existing code would have never worked. It doesn't look like aiohttp.ClientSession ever took a proxy arg -- so I believe this was always broken. I came across while using kubernetes-asyncio.

Issue #9995 is also the cause of tomplus/kubernetes_asyncio#90

[ntextreme3]

@kenjones-cisco as part of technical committee for python

[newly12]

Hi,

is there any plan to get this PR reviewed and merged?

[ntextreme3]

@newly12 openapi-generator has an equivalent fix. I tried and it seems to work good as a substitute of this repo, and has a bunch of other fixes I was looking for too.