Blender script for EC2 GPU rendering.

blender.py

import bpy

bpy.context.user_preferences.system.compute_device_type = 'CUDA'

for scene in bpy.data.scenes:
    scene.render.resolution_x = 1920
    scene.render.resolution_y = 1080
    scene.render.image_settings.file_format = 'PNG'
    scene.render.resolution_percentage = 100
    scene.render.tile_x = 1024
    scene.render.tile_y = 1024
    scene.cycles.samples = 1000
    scene.cycles.device = 'GPU'

bpy.ops.render.render(animation=False, write_still=True)
~