一般是训练一个binary的二分类任务
:param label1
:param label2
'''
x_train, y_train, x_test, y_test = return_part_mnist([label1, label2])
print(np.shape(x_train), np.shape(y_train), np.shape(x_test), np.shape(y_test))
y_train[y_train == label1] = 0
y_train[y_train == label2] = 1
y_test[y_test == label1] = 0
y_test[y_test == label2] = 1
print(y_train[:128])
print(y_test[:128])