A very simple example plugin, demonstrating how to polyfill PocketMine-MP's recently removed PluginTask class, for really lazy people.
This seems pointless to me, since you'll have to update code anyway.
Also, the PluginTask class was never very useful to begin with because you couldn't typehint $owner or getOwner() without breaking it.
However, here's the proof that it can be done, if you want to do it for some reason.
Public domain. I don't care what you do with this code, copy, modify, redistribute, mutilate, misuse, sell or whatever you please.