title: alternate CSV row deletion
body: <p>I have a csv file as follows:</p>
  
  <pre><code>gindex
  1
  1
  2
  2
  3
  3
  7
  7
  </code></pre>
  
  <p>I printed each element twice by mistake. How can I delete each repeated row and get the following results:</p>
  
  <pre><code>gindex
  1
  2
  3
  7
  </code></pre>