Python - parse xml with lxml trouble

Question

I've found a lot of questions on this issue but nothing I saw fits mine. I'm new to lxml so need some help.

my users.xml file:

<?xml version="1.0" encoding="UTF-8"?>

<root>
    <user>
    <login>elena</login>
    <password>elena</password>
    <group>1</group>
    </user>

    <user>
    <login>anele</login>
    <password>anele</password>
    <group>2</group>
    </user>
</root>

the trouble function:

def analize_data(login):
   doc = etree.parse("/myapp/users.xml")   
   for elem in doc.iter(tag='login'):       
       if elem.text == login:
          parent = elem.getparent()
          group = etree.SubElement(parent, 'group')
          return group.text

What I need: to find a user tag with login passed to function and get the text of group subelement of this user. But this function returns None when testing. What am I doing wrong and how to fix it?

I'm new to all these things, so need help. Thanks in advance!

Answer 1

Try using:

group = parent.iterchildren(tag="group").next()

etree.SubElement does something completely different:

This function creates an element instance, and appends it to an existing element.

Which is clearly not what you want.