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# for http://blender.stackexchange.com/q/65143/3710

bl_info = {
    "name": "Test",
    "description": "Set Background Image Opacity in 3D View to 1 at Startup",
    "author": "poor",
    "version": (0, 0, 1),
    "blender": (2, 70, 0),
    "location": "3D View",
    "warning": "", # used for warning icon and text in addons panel
    "wiki_url": "",
    "tracker_url": "",
    "category": "Development"
}


import bpy
from bpy.app.handlers import persistent

@persistent
def load_handler(dummy):

    # only apply to startup
    if not bpy.data.filepath:
        return

    for area in bpy.context.screen.areas:
        if area.type == 'VIEW_3D':
            space_data = area.spaces.active
            bg_imgs = space_data.background_images
            for img in bg_imgs:
                img.opacity = 1
            break
    
def register():
    bpy.app.handlers.load_post.append(load_handler)   

def unregister():
    bpy.app.handlers.load_post.remove(load_handler)
    

if __name__ == "__main__":
    register()