Python是什么东西？详细解读Python编程语言的特点与应用

import requests
from bs4 import BeautifulSoup

url = 'https://www.example.com'
response = requests.get(url)
soup = BeautifulSoup(response.text, 'html.parser')

# 获取网页标题
title = soup.title.string
print('网页标题：', title)

# 获取所有链接
links = soup.find_all('a')
for link in links:
    print(link.get('href'))

import pandas as pd

data = {'Name': ['Alice', 'Bob', 'Charlie'],
        'Age': [25, 30, 35],
        'Gender': ['F', 'M', 'M']}
df = pd.DataFrame(data)

# 统计年龄平均值
avg_age = df['Age'].mean()
print('平均年龄：', avg_age)

# 将数据写入CSV文件
df.to_csv('data.csv', index=False)

from sklearn import datasets
from sklearn.model_selection import train_test_split
from sklearn.neighbors import KNeighborsClassifier

iris = datasets.load_iris()
X_train, X_test, y_train, y_test = train_test_split(iris.data, iris.target, test_size=0.3, random_state=42)

knn = KNeighborsClassifier(n_neighbors=3)
knn.fit(X_train, y_train)

accuracy = knn.score(X_test, y_test)
print('准确率：', accuracy)