public async static Task<TwitterResponseCollection<Tweet>> GetFavourites(this ITwitterSession session, string screenName = "", int userId = 0, long sinceId = 0, long maxId = 0, int count = 20 )
{
var parameters = new TwitterParametersCollection();
parameters.Create(count:count,include_entities:true,since_id:sinceId,max_id:maxId, user_id:userId, screen_name:screenName);
var url = TwitterApi.Resolve("/1.1/favorites/list.json");
return await session.GetAsync(url, parameters)
.ContinueWith(c => c.MapToMany<Tweet>());
}