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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 comment(self, body):
 """Adds a comment to the issue. :params body: body, content of the comment :returns: issue object :rtype: :class:`exreporter.stores.github.GithubIssue` """

        self.github_request.comment(issue=self, body=body)

        if self.state == 'closed':
            self.open_issue()
        return self