package Ġcom . nr kt . student course graphql . repository Ċ Ċ import Ġcom . nr kt . student course graphql . model . Course Ċ import Ġorg . springframework . data . repository . Crud Repository Ċ Ċ interface ĠCourse Repository Ġ: ĠCr ud Repository < Course , ĠString > Ġ{ ĊĠĠĠ Ġfun ĠfindAll ById In ( course Id : ĠSet < String >): ĠSet < Course > Ċ }