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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_reaction(self, channel_id, timestamp, reaction_name, **kwargs):
 """ Send a reaction to a message using slack Event API """

        params = {
            "post_data": {
                "name": reaction_name,
                "channel": channel_id,
                "timestamp": timestamp,
            }
        }
        params["post_data"].update(kwargs)

        return self.api_call("reactions.add", **params)