Animation Nodes - how to remove with python command As far as I know, you can run a command in the bar button to remove animation node trees. But I would like to automate this with another script, for rigging purposes. 

This doesn't work:

bpy.ops.an.remove_node_tree("nodetreename")


As far as I know, there is an error Invoking the right window? 

Any clue how to script this?
You should be able to do it like so:

bpy.data.node_groups.remove(bpy.data.node_groups["tree name"])