title: Python json.loads fails with `ValueError: Invalid control character at: line 1 column 33 (char 33)`
body: <p>I have a string like this:</p>
  
  <pre><code>s = u"""{"desc": "\u73cd\u54c1\u7f51-\u5168\u7403\u6f6e\u6d41\u5962\u54c1\u7f51\u7edc\u96f6\u552e\u5546 &lt;br \/&gt;\r\nhttp:\/\/www.zhenpin.com\/ &lt;br \/&gt;\r\n&lt;br \/&gt;\r\n200\u591a\u4e2a\u56fd\u9645\u4e00\u7ebf\u54c1\u724c\uff0c\u9876\u7ea7\u4e70\u624b\u5168\u7403\u91c7\u8d2d\uff0c100%\u6b63\u54c1\u4fdd\u969c\uff0c7\u5929\u65e0\u6761\u2026"}"""
  </code></pre>
  
  <p><code>json.loads(s)</code> returns error message like this:</p>
  
  <pre><code>ValueError: Invalid control character at: line 1 column 33 (char 33)
  </code></pre>
  
  <p>Why does this error occur? How can I solve this problem?</p>