I can get not-well-formed XML output (attribute name must not be empty string):

<?xml version="1.0" encoding="iso-8859-1"?>
<root ="v_for_empty_name" k1="v1"></root>

AttributeImpl must ignore dict entries that may not be cast to valid XML attributes.

Code:

#!/usr/bin/python

from xml.sax.xmlreader import AttributesImpl as Attrs
from xml.sax.saxutils import XMLGenerator as Gen

g = Gen()
a = Attrs(dict([('k1','v1'),('','v_for_empty_name')]))
g.startDocument()
g.startElement('root',a)
g.endElement('root')
g.endDocument()
print