def system_methodSignature(self, method_name):

        # See http://xmlrpc.usefulinc.com/doc/sysmethodsig.html

        return 'signatures not supported'
system.methodSignature('add') => [double, int, int]
dataset/ETHPy150Open kleientertainment/ds_mod_tools/pkg/win32/Python27/Lib/SimpleXMLRPCServer.py/SimpleXMLRPCDispatcher.system_methodSignature