I ran into a situation recently where I needed to pass "None" as a value to some code which runs under the SimpleXMLRPCServer in the Python standard library. I immediately got a Fault something like this:

<Fault 1: 'exceptions.TypeError:cannot marshal None unless allow_none is enabled'>

I tried turning on allow_none by putting something like this in my XMLRPC client:

xmlrpclib.ServerProxy("http://localhost:8000", allow_none=1)

I never got this quite working, but by googling around, it seems that the XMLRPC spec doesn't have support for a None datatype. I anticipate that I won't need "None" much, but when you need it, you need it. I figured I could kludge something, but why?

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