xml = """<?xml version="1.0" encoding="UTF-8"?>
<ISBNdb server_time="2005-02-25T23:03:41">
 <BookList total_results="1" page_size="10" page_number="1" shown_results="1">
  <BookData book_id="somebook" isbn="0123456789">
   <Title>Interesting Book</Title>
   <TitleLong>Interesting Book: Read it or else..</TitleLong>
   <AuthorsText>John Doe</AuthorsText>
   <PublisherText>Acme Publishing</PublisherText>
  </BookData>
 </BookList>
</ISBNdb>"""
for book in tree.iterfind('BookList/BookData'):
    print('isbn:', book.attrib['isbn'])
for child in book.getchildren():
    pass
Best way to parse xml in Appengine with Python