I'm really newbie at blender. So I want to change an object from a python script.
If I create a new project (Ctrl+N) and open python console, I can changing position of vertices:
bpy.data.meshes['Cube'].vertices.co.z += 20
But if I'm using .blend file with mesh from here: http://www.blender-models.com/model-downloads/humans/id/head-mesh/ I can changing vertices too
What I'm doing wrong.