title: TypeError: must be str, not list
body: <p>the problem is output result is not save in csv file.
  I'm using this code to weight-age the words positive and negative.I want to save in the csv file.Firstly, read the csv file ,apply tf-idf and output display on shell,but error disply when result write in csv file.  </p>
  
  <pre><code>for i, blob in enumerate(bloblist):
      print("Top words in document {}".format(i + 1))
      scores = {word: tfidf(word, blob, bloblist) for word in blob.words}
      sorted_words = sorted(scores.items(), reverse=True)
      print(sorted_words)
      final = open("tfidf.csv", "w").write(sorted_words)
      print(final)
      print("done")
  </code></pre>
  
  <p>The error is:</p>
  
  <pre><code>   Top words in document 1
     Traceback (most recent call last):
     File "C:\Python34\webcrawler-Final.py", line 38, in &lt;module&gt;
     final = open("tfidf.csv", "w").write(sorted_words)
     TypeError: must be str, not list
  </code></pre>