title: ElementTree findtext doesn't find leaf nodes
body: <p>I'm using ElementTree to scan an XML string pulled from a text file.</p>
  
  <pre><code>&lt;root&gt;
      &lt;branch_a&gt;
          &lt;leaf&gt;foo&lt;/leaf&gt;
      &lt;/branch_a&gt;
      &lt;branch_b&gt;
          &lt;another_leaf&gt;bar&lt;/another_leaf&gt;
      &lt;/branch_b&gt;
  &lt;/root&gt;
  </code></pre>
  
  <p>When I parse it and try to find the leaf nodes, I don't get any result:</p>
  
  <pre><code>&gt;&gt;&gt; elem_tree = xml.etree.ElementTree.fromstring(xml_string)
  &gt;&gt;&gt; leaf_text = elem_tree.findtext('leaf')
  &gt;&gt;&gt; leaf_text is None
  True
  </code></pre>
  
  <p>But when I traverse the tree, everything works fine:</p>
  
  <pre><code>&gt;&gt;&gt; elem_tree.findtext('branch_a/leaf')
  'foo'
  
  &gt;&gt;&gt; branch = elem_tree.find('branch_a')
  &gt;&gt;&gt; branch.findtext('leaf')
  'foo'
  </code></pre>
  
  <p>Is there a way to have ElementTree scan the whole tree for me?  My branch names are dynamic, the leaf I'm looking for could live under any branch.</p>
  
  <p>I was able to do this with minidom, but ran into other limitations.  Here's what I was doing there, for reference (error checking stripped out).</p>
  
  <pre><code>&gt;&gt;&gt; xml_doc = xml.dom.minidom.parseString(xml_string)
  &gt;&gt;&gt; leaf_node = xml_doc.getElementsByTagName('leaf')
  &gt;&gt;&gt; leaf_node[0].firstChild.nodeValue
  'foo'
  </code></pre>