title: Append to text file repeatedly
body: <p>I'm writing to the same text file multiple times during a python program. How to write new contents at the end of text file?  That is I need always to place the pointer to the end of lines of the "out" file and write the new text. </p>
  
  <p>I have tried the following, which didn't work?</p>
  
  <pre><code>out.seek(0, 1)
  </code></pre>