def by_summoner_id summoner_id
      result = perform_request api_url "masteries/by-summoner/#{summoner_id}"
      result["pages"].map { |p| DynamicModel.new p }
    end
def by_summoner_id summoner_id
      result = perform_request api_url "masteries/by-summoner/#{summoner_id}"
      result["pages"].map { |p| DynamicModel.new p }
    end
Get mastery pages for a given summoner ID
 @param [Integer] summoner_id Summoner ID
 @return [Array<DynamicModel>] Mastery pages