request a URL and parse the response in Python
<p>I'm migrating a utility tool from Java to Python and I'm new to Python. I want to know the best way to do these simple and common tasks in Python:</p>

<ol>
<li>Build a URL with all parameters encoded correctly(using UTF8). </li>
<li>Request the URL and parse the XML response. </li>
<li>Find any node with a tag name "Foo"  </li>
<li>Find any node with a attribute Foo="Bar"</li>
</ol>

<p>I need to do all these things using Python 2.7.3 API only (without any third-party module or library).</p>
