With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Valerian and the City of a Thousand Planets refused to cast Rihanna.
text_B: Up on the Roof is a musical by Simon Moore and Jane Prowse , which follows a decade in the lives of five friends who form an a cappella singing group at university .. musical. musical theatre. Simon Moore. Simon Moore ( writer ). Jane Prowse. Jane Prowse. a cappella. a cappella. The show was first staged in 1987 in London and starred Mark McGann and Gary Olsen , and it was nominated for an Olivier Award for Best Musical and McGann and Olsen were nominated for best actor in a musical .. musical. musical theatre. Mark McGann. Mark McGann. Gary Olsen. Gary Olsen. Olivier Award. Olivier Award. It was revived at the Queen 's Theatre , Hornchurch in May and June 2006 .. Hornchurch. Hornchurch. The show was made into a film in 1997 starring Adrian Lester .. 1997 in film. Adrian Lester. Adrian Lester
not_related.