James: Professer McGonagall, how do you become an animagus?

Sirius: Hypothetically

McGonagall: ... I can't tell you. I'm sorry.

James: Oh

McGonagall: I also can't tell you that in the restricted section there is a book about becoming an animagus called True Animagus transformation. I also can't tell you that Filch will be away on Saturday 1-3 am.

Sirius: *scribbling this down*

McGonagall: You must understand I am not allowed to tell you such things.

James: We totally understand, Professor.