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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 addComment(self, comment):
 """ adds a comment to a given item. Must be authenticated """

        url = "%s/addComment" % self.root
        params = {
            "f" : "json",
            "comment" : comment
        }
        return self._post(url, params, proxy_port=self._proxy_port,
                             securityHandler=self._securityHandler,
                             proxy_url=self._proxy_url)