如何测量Python的scikit-learn中分类算法的执行时间？

import time
from sklearn import datasets
from sklearn.model_selection import train_test_split
from sklearn import svm

# 加载数据集
iris = datasets.load_iris()
X = iris.data
y = iris.target

# 划分数据集
X_train, X_test, y_train, y_test = train_test_split(X, y, test_size=0.2, random_state=42)

# 创建分类器
clf = svm.SVC()

# 记录开始时间
start_time = time.time()

# 拟合分类器
clf.fit(X_train, y_train)

# 记录结束时间
end_time = time.time()

# 计算执行时间
execution_time = end_time - start_time

print("分类算法的执行时间为：", execution_time, "秒")