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main.py

from typing import Optional


def func(x:int)->None:
    pass
    
async def main()-> None:
    geohub_pageid: Optional[int] = None

    async def x()-> int:    
        geohub_pageid = 123  
        return geohub_pageid

    if geohub_pageid:
        func() #hover to see 'Type analysis indicates code is unreachable'