You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: fixity_checks_controller.rb
    path of file: ./repos/hyrax/app/controllers/hyrax
    
    the code of the file until where you have to start completion: # frozen_string_literal: true
    
    def fixity_check_service
      # We are calling `async_jobs: false` to ensure we get a fixity result to
      # return even if there are no 'fresh' ones on record. Otherwise, we'd
      # have to sometimes return a 'in progress' status for some bytestreams,
      # which is a possible future enhancement.
      @fixity_check_service ||=
        FileSetFixityCheckService.new(::FileSet.find(params[:file_set_id]), async_jobs: false)
    end