title: Read/Write CSV as binary with Python
body: <p>I just found out that I can save space\ speed up reads of CSV files.  </p>
  
  <p>Using the answer of my previous question 
  <a href="https://stackoverflow.com/questions/3710263/how-do-i-create-a-csv-file-from-database-in-python">How do I create a CSV file from database in Python?</a></p>
  
  <p>And 'wb' for opens</p>
  
  <pre><code>  w = csv.writer(open(Fn,'wb'),dialect='excel')
  </code></pre>
  
  <p>How can I open all files in a directory and saves all files with the same name as starting name and use 'wb' to reformat all files. I guess convert all CSV's to binary CSV's. </p>