Requests 是 Python 中一个广受欢迎的 HTTP 库，它可以方便地发送 HTTP 请求，并处理 HTTP 响应。下面是 Requests 库的一些常用用法：

1. 发送 GET 请求：

import requests

response = requests.get('https://www.example.com')
print(response.text)

2. 发送 POST 请求：

import requests

data = {'username': 'example', 'password': '123456'}
response = requests.post('https://www.example.com/login', data=data)
print(response.text)

3. 添加请求头：

import requests

headers = {'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/58.0.3029.110 Safari/537.3'}
response = requests.get('https://www.example.com', headers=headers)
print(response.text)

4. 发送带参数的请求：

import requests

params = {'key': 'value'}
response = requests.get('https://www.example.com', params=params)
print(response.url)

5. 处理响应：

import requests

response = requests.get('https://www.example.com')
print(response.status_code)
print(response.headers)
print(response.cookies)

6. 处理异常：

import requests

try:
    response = requests.get('https://www.example.com')
    response.raise_for_status()
except requests.exceptions.HTTPError as e:
    print(e)
except requests.exceptions.ConnectionError as e:
    print(e)
except requests.exceptions.Timeout as e:
    print(e)
except requests.exceptions.RequestException as e:
    print(e)