private IEnumerable <ResponseMessage> FlickrHandler(IncomingMessage message, IValidHandle matchedHandle)
        {
            string searchTerm = message.TargetedText.Substring(matchedHandle.HandleHelpText.Length).Trim();

            if (string.IsNullOrEmpty(searchTerm))
            {
                yield return(message.ReplyToChannel($"Please give me something to search, e.g. {matchedHandle} trains"));
            }
            else
            {
                yield return(message.IndicateTypingOnChannel());

                string apiKey = _configReader.GetConfigEntry <string>("flickr:apiKey");

                if (string.IsNullOrEmpty(apiKey))
                {
                    _statsPlugin.IncrementState("Flickr:Failed");
                    yield return(message.ReplyToChannel("Woops, looks like a Flickr API Key has not been entered. Please ask the admin to fix this"));
                }
                else
                {
                    var flickr = new Flickr(apiKey);

                    var options = new PhotoSearchOptions {
                        Tags = searchTerm, PerPage = 50, Page = 1
                    };
                    PhotoCollection photos = flickr.PhotosSearch(options);

                    if (photos.Any())
                    {
                        _statsPlugin.IncrementState("Flickr:Sent");

                        int   i          = new Random().Next(0, photos.Count);
                        Photo photo      = photos[i];
                        var   attachment = new Attachment
                        {
                            AuthorName = photo.OwnerName,
                            Fallback   = photo.Description,
                            ImageUrl   = photo.LargeUrl,
                            ThumbUrl   = photo.ThumbnailUrl
                        };

                        yield return(message.ReplyToChannel($"Here is your picture about '{searchTerm}'", attachment));
                    }
                    else
                    {
                        _statsPlugin.IncrementState("Flickr:Failed");
                        yield return(message.ReplyToChannel($"Sorry @{message.Username}, I couldn't find anything about {searchTerm}"));
                    }
                }
            }
        }