title: Copy directory contents into a directory with python
body: <p>I have a directory /a/b/c that has files and subdirectories.
  I need to copy the /a/b/c/* in the /x/y/z directory. What python methods can I use?</p>
  
  <p>I tried <code>shutil.copytree("a/b/c", "/x/y/z")</code>, but python tries to create /x/y/z and raises an <code>error "Directory exists"</code>.</p>