How can I change Blender 2.8 Preference via Python I am trying to find out how to read/set values for Blender 2.8 Preferences with python , for example before 2.8 to change the gizmo size( previously known as manipulator size) to 10 

bpy.context.user_preferences.view.manipulator_size = 10


the user_preferences class doesn't seam to exist anymore,

I tried reading the api doc but it's not clear to me, i feel like i am missing something really simple

https://docs.blender.org/api/blender2.8/bpy.types.PreferencesView.html#bpy.types.PreferencesView
This works...

bpy.context.preferences.view.gizmo_size=101