title: "XML or text declaration not at start of entity: line 2, column 0" when calling ElementTree.parse
body: <p><a href="https://docs.python.org/2/library/xml.etree.elementtree.html#xml.etree.ElementTree.parse" rel="noreferrer"><code>ElementTree.parse()</code></a> fails in the simple example below with the error</p>
  
  <blockquote>
    <p>xml.etree.ElementTree.ParseError: XML or text declaration not at start of entity: line 2, column 0</p>
  </blockquote>
  
  <p>The XML looks valid and the code is simple, so what am I doing wrong?</p>
  
  <pre><code>xmlExample = """
  &lt;?xml version="1.0"?&gt;
  &lt;data&gt;
      stuff
  &lt;/data&gt;
  """
  import io
  source = io.StringIO(xmlExample)
  import xml.etree.ElementTree as ET
  tree = ET.parse(source)
  </code></pre>