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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 unsubscribe(self):
 """Unsubscribes this subscriber from the associated list."""

        body = {
            "EmailAddress": self.email_address}
        response = self._post("/subscribers/%s/unsubscribe.json" %
                              self.list_id, json.dumps(body))