Is it possible to enable backdrop using Python when running Blender without GUI? I am trying to enable backdrop in Blender using Python and using Blender's Python API (no GUI) but it seems that it is not as straight-forward as I thought. I know how to enable Use Nodes via bpy.context.scene.use_nodes = True and just need to enable backdrop. The most relevant Python documentation for backdrop Here is a bit unclear and I do not know exactly how I can enable backdropping through the NodeSpaceEditor class. Can someone explain how I can do that? 

Update: it turns out that the Python documentation is useful when you are running Blender with the GUI. I need to enable backdrop when I am running Blender in the background.

The hard way is to compile Blender from scratch and enable backdropping by modifying the source code as explained here but this is too much of work. I hope there is a way to do it using Blender's Python API.
You can set this property, you just have to know which area is the node editor. Like this:

import bpy

def get_node_editor_area():
    """
    Get the index of the area containing the compositor
    """
    for i in range(len(bpy.context.screen.areas)):
        area = bpy.context.screen.areas[i]
        if area.type == 'NODE_EDITOR':
            return i

area_index = get_node_editor_area()
bpy.context.screen.areas[area_index].spaces[0].show_backdrop = True


If this is for an addon and the user will have the mouse in the node editor area when this function is called, I think you could use bpy.context.space_data.show_backdrop = True instead.