The theatricalist use of lighting in brecht’s didactic theatre calls for

The theatricalist use of lighting in brecht's didactic theater calls for : 
the lighting instruments being exposed and placed in full view of the audience
Thetricalist tend to prefer exposing the elements of theater (such as lightning and music instrument) to make audience member aware of its contribution to the performance.

Normally it is at the top left, above where the music starts.

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