Python-сообщество

<?xml version="1.0" encoding="utf-8"?>
<yandexsearch version="1.0">
  <request>
    <query>
    </query>
    <page>
      0
    </page>
    <sortby order="ascending" priority="no">
      tm
    </sortby>
    <maxpassages>
    </maxpassages>
    <groupings>
      <groupby attr="" mode="flat" groups-on-page="10" docs-in-group="1" curcateg="-1" />
    </groupings>
  </request>
  <response date="20160115T093915">
    <error code="2">
      Задан пустой поисковый запрос
    </error>
  </response>
</yandexsearch>

root = et.fromstring(xml)
root.findall('error') // []

print root.find("response").findall("error")