title: How to construct the header when a single key has multiple possible value?
body: <p>Now I wish to scrape a web page with python and when I look into the header constructed by the web browser, there are several keys have multiple values:</p>
  
  <pre><code>Accept:text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8
  Accept-Encoding:gzip, deflate, sdch, br
  Accept-Language:zh-CN,zh;q=0.8,zh-TW;q=0.6
  </code></pre>
  
  <p>I wonder how should I construct the dictionary, <code>header</code>? Should I use </p>
  
  <pre><code>header = {'Accept': 'text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8', ...}
  </code></pre>
  
  <p>? Thank you in advance!</p>