Do a copy of an attribute list.

def copyPropList(self, cur):
        """Do a copy of an attribute list. """
        if cur is None: cur__o = None
        else: cur__o = cur._o
        ret = libxml2mod.xmlCopyPropList(self._o, cur__o)
        if ret is None:raise treeError('xmlCopyPropList() failed')
        __tmp = xmlAttr(_obj=ret)
        return __tmp