There is also the excellent lxml library. You can query the tree with xpath or if you are familiar with css you can select elements with cssselect.
In [1]: from lxml import etree
In [2]: from StringIO import StringIO
In [3]: f = StringIO('<foo><bar id="1">hello</bar><bar id="2">world</bar></foo>')
In [4]: tree = etree.parse(f)
In [5]: r = tree.xpath('/foo/bar')
In [6]: print len(r)
2
In [7]: for elem in r:
....: print elem.get('id'), elem.text
1 hello
2 world