You will be given a definition of a task first, then some input of the task.
In this task, you're given passages that contain mentions of the quantity of a particular object and are supposed to find out the answer for a given question. Craft one correct answer to the question given in input. Make sure your correct answer is consistent with the context, and properly gives the exact number relating to the query.
 In your answer, use as few words as possible from the given context. To be less repetitive, please vary your language for each question.

Sentence: In September 2015 it was announced that Sam Smith and regular collaborator Jimmy Napes had written the film's title theme, "Writing's on the Wall", with Smith performing it for the film. Smith said the song came together in one session and that he and Napes wrote it in under half an hour before recording a demo. Satisfied with the quality, the demo was used in the final release. 
Question: How many recording sessions did it take to complete the song?
Output:
one