[XML-SIG] Default namespace

[Lars Marius Garshol]

* Juergen Hermann
| 
| What should the default namespace URI be bound to? u'' or None?

Do you mean what the namespace URI of elements with no namespace is?
It is None. 

Java SAX uses "" to avoid awkwardness in applications which would have
had to do a != null && a.equals("foo") had the default URI been None.
We decided to use None in Python, since Python has no such problems,
and since felt more natural.

I put in a mention of this in the documentation string for
ContentHandler now.

--Lars M.