code: def mine
      page = @client.get_nokogiri '/atstellar'
      class_links = page.css('a[href*="/S/course/"]').
          map { |link| Stellar::Course.from_link link, @client }.reject(&:nil?)
    end
docs: My classes.
   @return [Array] array with one Hash per class; Hashes have :number and
                   :url keys