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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 approve_task(self, task_id):
 """ Returns dict of tasks matching the provided filters """

        uri = 'tasks/%s' % task_id

        data = {"approved": True}

        resp, body = self.post(uri, json.dumps(data))
        self.expected_success(200, resp.status)
        body = json.loads(body)
        return rest_client.ResponseBody(resp, body)