一些注意事项：

1.看了Coursera上面的python教程，里面给了一个非常简单的示例，只传一个url就获取到响应报文。然而很多网站是不能只通过一个url就响应请求的，你还需要填写报文头部也就是header部分。

2.得到的报文里面中文字符都是bytes，十六进制的格式，需要用utf-8解码

3.巧用控制台找到页面内容真实的网址

其余的注意点我都写在注释里了，完整源码如下：

#爬取网易云音乐我的歌单里面所有歌曲的歌词

import json

import requests

import re

import urllib

from bs4 import *

url = "http://music.163.com/playlist?id=129816983"

headers = {"Host":" music.163.com",

"User-Agent":" Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:56.0) Gecko/20100101 Firefox/56.0",

#不必要的header属性可能会影响响应报文的编码方式，所以把它们注释掉

#"Accept":" text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8",

#"Accept-Language":" zh-CN,zh;q=0.8,en-US;q=0.5,en;q=0.3",

#"Referer":"http://music.163.com/",

#"Cookie": "JSESSIONID-WYYY=k52%2FPjMyNbX0v38jH2efUXwEIZpw2NagEUzwTX%2FgifMsoMswU6yo3NN%5C%2Bb9jCpsRFZIc6lvPUK9wEjgBzwM%2B1T%2FRyvRGHhqyWbdvEcugCbNqTihfxHK1el66fk%2BNntcSwGVOBMEwlcFDBusingcH76NIeAQwbC6h%5CcipxCdO8T5IfBVO%3A1510825875526; _iuqxldmzr_=32; _ntes_nnid=e5ec3ba6b841b9d3eadcb910066f4dcb,1510815153893; _ntes_nuid=e5ec3ba6b841b9d3eadcb910066f4dcb; __utma=94650624.1386008069.1510815154.1510815154.1510824076.2; __utmz=94650624.1510815154.1.1.utmcsr=baidu|utmccn=(organic)|utmcmd=organic; __utmb=94650624.2.10.1510824076; __utmc=94650624",

#"Connection": "keep-alive",

#"Upgrade-Insecure-Requests": "1"

}

#只传url不能获得响应，需要传header

request = urllib.request.Request(url,headers=headers)

response = urllib.request.urlopen(request)

#不decode的话text是十六进制，不是中文

html = response.read().decode('utf-8','ignore')

soup = BeautifulSoup(html)

#打开1.txt 把歌单中的歌词写入

f=open('C:/Users/liuxu/Desktop/myfavoritesong.txt','w',encoding='utf-8')

for item in soup.ul.children:

    #取出歌单里歌曲的id  形式为：/song?id=11111111

    song_id = item('a')[0].get("href",None)

    #利用正则表达式提取出song_id的数字部分sid

    pat = re.compile(r'[0-9].*$')

    sid = re.findall(pat,song_id)[0]

    #这里的url是真实的歌词页面

    url = "http://music.163.com/api/song/lyric?"+"id="+str(sid)+"&lv=1&kv=1&tv=-1"

    html = requests.post(url)

    json_obj = html.text

    #歌词是一个json对象 解析它

    j = json.loads(json_obj)

    try:

        lyric = j['lrc']['lyric']

    except KeyError:

        lyric = "无歌词"

    pat = re.compile(r'\[.*\]')

    lrc = re.sub(pat,"",lyric)

    lrc = lrc.strip()

    #print(lrc)

    f.write(lrc)

f.close()