running a .py by double-clicking is not working
<p>I'm using Windows XP.</p>

<p>When I double click the Launch_PyDemos.pyw from the book Programming Python, nothing happens. When I try to run Launch_PyDemos.pyw from command-line, I get the error message:</p>

<pre><code>Traceback (most recent call last):
  File "PyDemos2.pyw", line 41, in &lt;module&gt;
    from PP3E.Gui.Tools.windows import MainWindow    # a Tk with icon, title, quit
ImportError: No module named PP3E.Gui.Tools.windows
</code></pre>

<p>When I set the PythonPath enviroment variable to the PP3E folder, nothing happens. When I append the PP3E folder to the Path enviroment variable, nothing happens. When I copy the PP3E directory tree to the site-packages folder in your Python source library, nothing happens.</p>

<p>What is going on?</p>
