如何简化循环中请求头编写？每次请求需随机User Agent

我想简化请求头的编写方式——现在每个循环里都要重复写完整的请求头字典，目的是每次请求都随机生成新的User Agent，但我不想在每个循环里都重复写这段代码。

原代码示例：

for example in examples:
    headers = {
    'accept': '*/*',
    'accept-language': 'en-GB,en-US;q=0.9,en;q=0.8,es;q=0.7,ru;q=0.6',
    'referer': 'https://www.google.com/',
    'user-agent': random.choice(all_user_agents),
    }
    response = request.get(url, headers=headers)

while 10 > i:
    headers = {
    'accept': '*/*',
    'accept-language': 'en-GB,en-US;q=0.9,en;q=0.8,es;q=0.7,ru;q=0.6',
    'referer': 'https://www.google.com/',
    'user-agent': random.choice(all_user_agents),
    }
    response = request.get(url, headers=headers)

for test in tests:
    headers = {
    'accept': '*/*',
    'accept-language': 'en-GB,en-US;q=0.9,en;q=0.8,es;q=0.7,ru;q=0.6',
    'referer': 'https://www.google.com/',
    'user-agent': random.choice(all_user_agents),
    }
    response = request.get(url, headers=headers)

方法1：封装生成请求头的函数 #

把固定的请求头模板抽离出来，写一个函数每次返回带随机UA的完整请求头，避免重复编写字典结构：

import random

# 定义固定的基础请求头（只写一次）
BASE_HEADERS = {
    'accept': '*/*',
    'accept-language': 'en-GB,en-US;q=0.9,en;q=0.8,es;q=0.7,ru;q=0.6',
    'referer': 'https://www.google.com/'
}

def get_random_headers():
    # 复制基础头，防止修改原字典影响后续请求
    headers = BASE_HEADERS.copy()
    headers['user-agent'] = random.choice(all_user_agents)
    return headers

# 循环中直接调用函数获取请求头
for example in examples:
    response = request.get(url, headers=get_random_headers())

while 10 > i:
    response = request.get(url, headers=get_random_headers())

for test in tests:
    response = request.get(url, headers=get_random_headers())

方法2：复用基础字典动态添加UA #

如果不想额外写函数，也可以在每次请求时复制基础字典，再添加随机UA，代码更轻量化：

BASE_HEADERS = {
    'accept': '*/*',
    'accept-language': 'en-GB,en-US;q=0.9,en;q=0.8,es;q=0.7,ru;q=0.6',
    'referer': 'https://www.google.com/'
}

for example in examples:
    headers = BASE_HEADERS.copy()
    headers['user-agent'] = random.choice(all_user_agents)
    response = request.get(url, headers=headers)

while 10 > i:
    headers = BASE_HEADERS.copy()
    headers['user-agent'] = random.choice(all_user_agents)
    response = request.get(url, headers=headers)

for test in tests:
    headers = BASE_HEADERS.copy()
    headers['user-agent'] = random.choice(all_user_agents)
    response = request.get(url, headers=headers)

方法3：封装完整的请求方法 #

如果重复的不仅是请求头，连request.get的调用逻辑也一致，可以把整个请求逻辑封装成函数，进一步简化代码：

BASE_HEADERS = {
    'accept': '*/*',
    'accept-language': 'en-GB,en-US;q=0.9,en;q=0.8,es;q=0.7,ru;q=0.6',
    'referer': 'https://www.google.com/'
}

def get_with_random_ua(url):
    headers = BASE_HEADERS.copy()
    headers['user-agent'] = random.choice(all_user_agents)
    return request.get(url, headers=headers)

# 调用时只需传入URL即可
for example in examples:
    response = get_with_random_ua(url)

while 10 > i:
    response = get_with_random_ua(url)

for test in tests:
    response = get_with_random_ua(url)

内容的提问来源于stack exchange，提问作者BQuist