curl -X POST -d '{
"trainUrl":"data://weka/WekaSampleCollection/cpu.arff",
"modelUrl":"data://.algo/temp/model.txt",
"mode":"train"
}' -H 'Content-Type: application/json' -H 'Authorization: Simple YOUR_API_KEY' https://api.algorithmia.com/v1/algo/weka/XMeansClusterer/0.1.3