<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def get(self, request, uri):
 """ Return published node or specified version. JSON Response: {uri: x, content: y} """

        uri = self.decode_uri(uri)
        node = cio.get(uri, lazy=False)

        if node.content is None:
            raise Http404

        return self.render_to_json({
            'uri': node.uri,
            'content': node.content
        })