Reason for the change
Python3.11 compatibility issues with running

Description
"@asyncio.coroutine" and "yield from" syntax no longer allowed in 3.11. Changed to "async" and "await" respectively.

Code examples
For example, changes made like this:

@asyncio.coroutine        <<<<-- REMOVED
async def _read_until(streamreader, delimiter): <<<<--- ADDED
    """Naive implementation of reading until a delimiter"""
    buffer = bytearray()
    while True:
        # c = yield from streamreader.read(1)  <<<<<<-- REMOVED
        c = await streamreader.read(1)   <<<<<< -- ADDED
        if c == b"":
            break  # EOF
        buffer.append(c[0])
        if c == delimiter:
            break
    return bytes(buffer)

Checklist

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References
I have a number of compatibility updates, made some for 3.10 as well last year. I wanted decreased verbosity in the export.
Happy to cherry pick what makes sense, but would like to see continued support track with Python versions.