Please document why the library wants Python >= 3.7. about adbus

[refi64]

I believe it uses variable annotations which are 3.7+ only.

[Kaveshnikov]

But in fact, I have no syntax errors in Python 3.6

[charleseidsness]

It will most likely work in Python 3.6, but all development and testing is using 3.7, we don't officially support any versions pre-3.7.

[socketpair]

I would recommend you to support Python 3.6 since 3.7 is too new for current LTS OSes.

[charleseidsness]

Good point, if someone uses this library for an application that is based on 3.6, and does some testing on 3.6 we'd be happy to update the minimum version requirements. We exclusively use 3.7 so aren't able to easily verify that there aren't issues using 3.6.