title: add row to existing csv file in python
body: <p>I want to use a function to add a row of information to an existing csv file. </p>
  
  <p><code>friend_info</code> will be a tuple including <code>[name, address, phone, DOB]</code></p>
  
  <p>I have this code</p>
  
  <pre><code>def add_friend(friend_info, friends_list):
      with open(friends_list, 'a') as fapp:
          writer = csv.writer(fapp)
          writer.writerow(friend_info)
  </code></pre>
  
  <p>for some reason this code is adding to the last line of the csv (I want it to start on a new line)</p>