Question: who is a pretty little liars season 7

title: Pretty Little Liars (season 7)
text: After receiving a job offer as the Rosewood High swim coach , Emily discovers that Paige has returned to Rosewood and is also a candidate for the job . Hanna is visited by Mrs. Grunwald , who warns her about Noel . Meanwhile , Alison goes back to work at Rosewood High , but finds it difficult after her students play a prank on her . Aria struggles with her relationship with Ezra after telling him she deleted a call that came from Nicole 's cellphone , and later , with Spencer , visits the doctor who delivered Mary 's baby in order to get answers . Aria buys a plane ticket for Ezra to get him closer to the latest news on Nicole , delaying their wedding . After not getting any help from the Liars , Hanna goes rogue and decides to work alone in an unknown plan to try and discover who `` A.D. '' is .