Question: Who wrote the eighteenth episode of the seventh season of "Pretty Little Liars", featuring Shay Mitchell as Emily?
Sentence (from "Pretty Little Liars: The Perfectionists"): Pretty Little Liars: The Perfectionists is a upcoming American teen drama television series developed by I. Marlene King, loosely based on the popular book series "The Perfectionists" written by Sara Shepard.
Relevant evidence: No