Cutting a reflex arc

A reflex arc is a list of parts in a row: a receptor, an afferent neuron, a synapse in the spinal cord, an efferent neuron and an effector. You will cut the arc at one part and see what is lost.

The idea. If any part of the arc is cut, the reflex is lost. The person still feels the stimulus if the impulse can reach the brain, which needs the receptor and the afferent neuron to work.

Your tasks.

1. Finish reflex_works. It gives True when the cut part is not in the arc, and False otherwise.
2. Finish feeling. It gives True when the person still feels the stimulus after the cut. The feeling is lost only when the receptor or the afferent neuron is cut.
3. Set lost_reflex_kept_feeling to the list of parts whose cut loses the reflex but keeps the feeling, in the order of the arc.