# Sets "Collision" flag on all faces in the current scene.
# To use:
#  - Open a Blender "Text Editor" window.
#  - Open this this script in the "Text Editor" window (File -> Open).
#  - Execute the script (File -> Run Python Script).

import Blender

for object in Blender.Scene.getCurrent().getChildren():
    if object.getType() == "Mesh":
        mesh = object.getData()
        for face in mesh.faces:
            face.mode |= Blender.NMesh.FaceModes.DYNAMIC
        mesh.update()

Blender.Redraw()