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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def newDocProp(self, name, value):
 """Create a new property carried by a document. """

        ret = libxml2mod.xmlNewDocProp(self._o, name, value)
        if ret is None:raise treeError('xmlNewDocProp() failed')
        __tmp = xmlAttr(_obj=ret)
        return __tmp