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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_comment(self, message):
 """ Comments on an issue, not on a particular line. """

        report_url = (
            'https://api.github.com/repos/%s/issues/%s/comments'
            % (self.repo_name, self.pr_number)
        )
        result = self.requester.post(report_url, {'body': message})
        if result.status_code >= 400:
            log.error("Error posting comment to github. %s", result.json())
        return result