title: Get the description of a status code in Python Requests
body: <p>I would like to be able to enter a server response code and have Requests tell me what the code means. For example, code 200 --> ok</p>
  
  <p>I found a link to the <a href="https://github.com/kennethreitz/requests/blob/master/requests/status_codes.py" rel="noreferrer">source code</a> which shows the dictionary structure of the codes and descriptions. I see that Requests will return a response code for a given description:</p>
  
  <pre><code>print requests.codes.processing  # returns 102
  print requests.codes.ok          # returns 200
  print requests.codes.not_found   # returns 404
  </code></pre>
  
  <p>But not the other way around:</p>
  
  <pre><code>print requests.codes[200]        # returns None
  print requests.codes.viewkeys()  # returns dict_keys([])
  print requests.codes.keys()      # returns []
  </code></pre>
  
  <p>I thought this would be a routine task, but cannot seem to find an answer to this in online searching, or in the <a href="http://docs.python-requests.org/en/latest/user/quickstart/" rel="noreferrer">documentation</a>.</p>