title: Comparing two .txt files using difflib in Python
body: <p>I am trying to compare two text files and output the first string in the comparison file that does not match but am having difficulty since I am very new to python.  Can anybody please give me a sample way to use this module.  </p>
  
  <p>When I try something like:</p>
  
  <pre><code>result = difflib.SequenceMatcher(None, testFile, comparisonFile)
  </code></pre>
  
  <p>I get an error saying object of type 'file' has no len.</p>