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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 sample_element(self, node, parent, module, path):
 """Create element under `parent`. Declare new namespace if necessary. """

        if path is None:
            return parent, module, None
        elif path == []:
            # GO ON
            pass
        else:
            if node.arg == path[0]:
                path = path[1:]
            else:
                return parent, module, None

        res = etree.SubElement(parent, node.arg)
        mm = node.main_module()
        if mm != module:
            res.attrib["xmlns"] = self.ns_uri[mm]
            module = mm
        return res, module, path