How to? Created a document and an element:

```
import xml.dom.minidom as d
a=d.Document()
b=a.createElement('test')

```

setIdAttribute doesn't work :(

```
b.setIdAttribute('something')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/lib/python2.6/xml/dom/minidom.py", line 835, in setIdAttribute
    self.setIdAttributeNode(idAttr)
  File "/usr/lib/python2.6/xml/dom/minidom.py", line 843, in setIdAttributeNode
    raise xml.dom.NotFoundErr()
xml.dom.NotFoundErr

```

And if I set this by hand, getElementById can't find it.

```
b.setAttribute('id', 'something')
a.getElementById('something')

```

What I have to do?