import matplotlib.pyplot as plt
import numpy as np
from sklearn import datasets, linear_model
# Create linear regression object
regr = linear_model.LinearRegression()
# Train the model using the training sets
regr.fit(X_train, y_train)
# how save ?????
# save here
保存经过训练的模型并在其他地方使用的最佳实践是什么?