W606: false positive when selecting async function from list by index

Using version 2.6.0 in a clean Docker container (python 3.8.2)

Code to reproduce:

import asyncio


async def a(p):
    print(p)


async def b():
    await [a][0]("hi")

if __name__ == "__main__":
    asyncio.run(b())

Output:

root@47c18858d18f:/app# python -m pycodestyle test.py
test.py:9:5: W606 'async' and 'await' are reserved keywords starting with Python 3.7
root@47c18858d18f:/app#

This appears similar to #811, which was also about false positives on W606.

Run the provided Python 3.8 reproduction with pycodestyle 2.6.0, then trace the W606 handling that reports the warning for the indexed async function call. Done means the example no longer produces a false-positive W606 diagnostic; add or update a regression test if the project’s existing test structure identifies one.