def doKmeans(X, nclust):
    model = KMeans(nclust)
    model.fit(X)
    clust_labels = model.predict(X)
    cent = model.cluster_centers_
    return (clust_labels, cent)

clust_labels, cent = doKmeans(df_new, 4)
kmeans = pd.DataFrame(clust_labels)

df_new.insert((df_new.shape[1]),'clusterNo',kmeans)