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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 newDocTextLen(self, content, len):
 """Creation of a new text node with an extra content length parameter. The text node pertain to a given document. """

        ret = libxml2mod.xmlNewDocTextLen(self._o, content, len)
        if ret is None:raise treeError('xmlNewDocTextLen() failed')
        __tmp = xmlNode(_obj=ret)
        return __tmp