title: how to append to a new row when writing to CSV file
body: <p>I want to append to a new row in my CSV file when i write to it.
  Current CSV file look like this:</p>
  
  <pre><code>a,b,c
  1,1,1
  </code></pre>
  
  <p>my code to append to CSV file:</p>
  
  <pre><code>with open('mycsvfile.csv','a') as f:
      writer=csv.writer(f)
      writer.writerow(['0','0','0'])
  </code></pre>
  
  <p>new mycsvfile:</p>
  
  <pre><code>a,b,c
  1,1,1,0,0,0
  </code></pre>
  
  <p>What i want:</p>
  
  <pre><code>a,b,c
  1,1,1
  0,0,0
  </code></pre>