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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 notify(self, msg, color='green', notify='true', message_format='text'):
 """Send notification to specified HipChat room"""

        self.message_dict = {
            'message': msg,
            'color': color,
            'notify': notify,
            'message_format': message_format,
        }
        if not self.debug:
            return requests.post(
                self.notification_url,
                json.dumps(self.message_dict),
                headers=self.headers
            )
        else:
            print('HipChat message: <{}>'.format(msg))
            return []