title: Python - Move line from one file to another
body: <p>I am attempting to read a text file, copy each line to a new file, and delete that line from the original file.  Not sure how to delete the line.  Any help is greatly appreciated.  Here is my code so far:</p>
  
  <pre><code>    with open("TestList_in.txt",'r+') as f:
          for lineNum in f:
              lineNum.replace("\n","")
              with open("TestList_done.txt","a") as done:
                  done.write(lineNum)
  </code></pre>