Vasya=model.fit(chank1,answer1)
a1=model.predict(Vasya,answer_t_1)

kf = KFold(n_splits=N)
for train, test in kf.split(X):
    print("%s %s" % (train, test))
    X_train, X_test, y_train, y_test = X[train], X[test], y[train], y[test]
    model.fit(X_train, y_train)
    ...

kf = KFold(n_splits=N)
results = cross_val_score(model, X, y, cv=kf)