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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 post(self, url, postParameters=None, urlParameters=None):
 """ Implement libgreader's interface for authenticated POST request """

        if self._action_token == None:
            self._action_token = self.get(ReaderUrl.ACTION_TOKEN_URL)

        if self._http == None:
            self._setupHttp()
        uri = url + "?" + self.getParameters(urlParameters)
        postParameters.update({'T':self._action_token})
        body = self.postParameters(postParameters)
        response, content = self._http.request(uri, "POST", body=body)
        return content