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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 update(self, body):
 """Update this comment. :param str body: (required) :returns: bool """

        json = None
        if body:
            json = self._json(self._post(self._api, data={'body': body}), 200)

        if json:
            self._update_(json)
            return True
        return False