title: outputting a CSV file from shell
body: <p>Hi I have an input file in this format. </p>
  
  <pre><code>[Header A]
  key1 value1
  key2 value2
  
  [Header B]
  header1    header2    header3   // separated by tab
  1            2          3     //separated by tab
  a            b          c     //separated by tab
  
  [Header C]
  a
  b
  c
  </code></pre>
  
  <p>I have to output whatever is in HeaderB as another csv file
  So the CSV file will look like</p>
  
  <pre><code>header1,header2,header3
  1,2,3
  a,b,c
  </code></pre>
  
  <p>I wrote a python script to do that but the requirement it to do it via a shell command. I don't have much idea about writing complicated shell commands. Can someone help me.</p>
  
  <p>Thanks</p>