public static async Task<PoisByFloor> GetPoisByFloor(string buid, string floor_number)
{
var r = new RequestPoisByFloor { access_token = "api_tester", buid = buid, floor_number = floor_number };
var response = await AnyPlaceClient.PostAsJsonAsync(new Uri(ServerBaseUri, "anyplace/mapping/pois/all_floor"), r);
var buildings = await response.Content.ReadAsAsync<PoisByFloor>();
IsDirty = true;
return buildings;
}