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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 _encode_content(self, uri, content):
 """ Join node uri and content as string and convert to bytes to ensure no pickling in memcached. """

        if content is None:
            content = self.NONE
        return smart_str('|'.join([six.text_type(uri), content]))