pyisnothing function?

[stevengj]

Seems pretty common to check if something is None in Python, but it is a bit awkward (and probably suboptimal) to check pyconvert(Bool, object == Py(nothing)). (Since None is a singleton object in Python, you can just check pointer equality.)

[cjdoris]

You can already do one of:

pyis(x, pybuiltins.None)  # 1ns
@py x === None  # 1ns
pyis(x, nothing)  # 20ns