cross_validators = [KFold(n_splits=K), # K = 25
ShuffleSplit(n_splits=5, test_size=.25, random_state=0),
LeaveOneOut()]
classifiers = [KNeighborsClassifier(n_neighbors=1),
KNeighborsClassifier(n_neighbors=3),
KNeighborsClassifier(n_neighbors=5),
BernoulliNB(),
SVC(kernel='linear')]