Python check type

Super simple question, but my mind is just not working today, I’m creating a custom ghpython component and want a quick check that what is being input is of type Plane, ie:

if type(x) == ‘Plane’:

Obviously, that code doesn’t return positive even if x is a plane, but for the life of me I can’t figure out what to put for the conditional (after the equal to)?

! This checks if the geometry originates from “Plane” container.
Or is something else wanted ?

from Rhino.Geometry import Plane as pl
if pl.GetType(x) == pl:
    print 'true'
    print 'false'

You can use Rhino.Geometry.Plane and the same for other geometries

Perfect, thanks for refreshing my memory.