title: Error in pymongo mapreduce example?
body: <p>I was trying to execute the example in &quot;http://api.mongodb.org/python/1.3/examples/map_reduce.html&quot;,I got the following error :</p>
  <blockquote>
  <p>File &quot;map_red.py&quot;, line 30, in </p>
  <p>if <strong>name</strong> == '<strong>main</strong>': main()</p>
  <p>File &quot;map_red.py&quot;, line 24, in main</p>
  <p>result = db.things.map_reduce(map, reduce )</p>
  <p>TypeError: map_reduce() takes at least 4 arguments (3 given)</p>
  </blockquote>
  <p>So I edited the code to look like this , but i dont see any output(I also replaced &quot;result&quot; with &quot;mr_result&quot; in find() but still there was no output!!)</p>
  <pre><code>result = db.things.map_reduce(map, reduce,{&quot;out&quot;: &quot;mr_results&quot;} )
  result_find = db.result.find()
  for doc in result_find:
      print doc
  </code></pre>