/// <summary>
/// Trains the pipeline with data stored in a filename.
/// </summary>
public ScikitPipeline Train(string loaderSettings, string filename,
string feature = "Feature", string label = null,
string weight = null, string groupId = null)
{
_loaderSettings = loaderSettings;
var loader = _env.CreateLoader(loaderSettings, new MultiFileSource(filename));
return(Train(loader));
}