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

[penn5]

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.