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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 mark_read(self):
 """ Mark notifications as read. CURRENT UNSUPPORTED: https://github.com/kippt/api-documentation/blob/master/endpoints/notifications/POST_notifications.md """

        # Obviously remove the exception when Kippt says the support it.
        raise NotImplementedError(
            "The Kippt API does not yet support marking notifications as read."
        )

        data = json.dumps({"action": "mark_seen"})
        r = requests.post(
            "https://kippt.com/api/notifications",
            headers=self.kippt.header,
            data=data
        )
        return (r.json())