Remove abandoned project pyannotate

[hofrob]

What is this (abandoned) Python project?

pyannotate has had its last update in 2019 and has major/breaking bugs.

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[LeoDog896]

Is there a good alternative that could be substituted in for pyannotate?

[hofrob]

Not that I know of, sadly. pytype (already in the list) is a usable alternative though.