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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 changePlanParticipation(self, plan, take_part=True):
 """ Changes participation in a plan :param plan: Plan to take part in or not :param take_part: Whether to take part in the plan :raises: FBchatException if request failed """

        data = {
            "event_reminder_id": plan.uid,
            "guest_state": "GOING" if take_part else "DECLINED",
            "acontext": ACONTEXT,
        }
        j = self._post(
            self.req_url.PLAN_PARTICIPATION, data, fix_request=True, as_json=True
        )