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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 _checkAuth(self, message, server_url):
 """Make a check_authentication request to verify this message. @returns: True if the request is valid. @rtype: bool """

        logging.info('Using OpenID check_authentication')
        request = self._createCheckAuthRequest(message)
        if request is None:
            return False
        try:
            response = self._makeKVPost(request, server_url)
        except (fetchers.HTTPFetchingError, ServerError) as e:
            e0 = e.args[0]
            logging.exception('check_authentication failed: %s' % e0)
            return False
        else:
            return self._processCheckAuthResponse(response, server_url)