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: repository_importer.rb
    path of file: ./repos/gitlabhq/lib/gitlab/bitbucket_import/importers
    
    the code of the file until where you have to start completion: # frozen_string_lite
    
        def execute
          log_info(import_stage: 'import_repository', message: 'starting import')

          if project.empty_repo?
            project.repository.import_repository(project.import_url)
            project.repository.fetch_as_mirror(project.import_url, refmap: refmap)

            validate_repository_size!

            set_default_branch
            update_clone_time
          end