I am trying to animate changing brightness of a point lamp using input data that I have. However, when I try to access the lamp's strength using

bpy.data.node_groups["Shader Nodetree"].nodes["Emission"].inputs[1].default_value

I get the error message:

Traceback (most recent call last):
File "<blender_console>", line 1, in <module>
KeyError: 'bpy_prop_collection[key]: key "Shader Nodetree" not found

Is there another way I can/should access and change the lamp's strength via Python?

  • $\begingroup$ you can find the answer here $\endgroup$ May 24, 2019 at 7:47

1 Answer 1


Yes, reach node_tree through lamp object bpy.data.lamps['lamp name'].node_tree.nodes.

  • $\begingroup$ This works great! I'm now trying to add keyframes for the changing lamp strength, what should go in the data_path parameter? $\endgroup$
    – wjkaufman
    Oct 4, 2015 at 22:17
  • $\begingroup$ My guess is 'default_value', since you keyframing a node input. $\endgroup$
    – kilbee
    Oct 4, 2015 at 22:24

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