def []=(url, value)
      case
        when store.respond_to?(:[]=)
          store[key_for(url)] = value
        when store.respond_to?(:set)
          store.set key_for(url), value
        when store.respond_to?(:write)
          store.write key_for(url), value
      end
    end
def []=(url, value)
      case
        when store.respond_to?(:[]=)
          store[key_for(url)] = value
        when store.respond_to?(:set)
          store.set key_for(url), value
        when store.respond_to?(:write)
          store.write key_for(url), value
      end
    end
Write to the Cache.