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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_op(self, id: str, path_data: Union[dict, None], post_data: Any) -> dict: """Modifies the ESI by looking up an operation id. Args: path: raw ESI URL path path_data: data to format the path with (can be None) post_data: data to send to ESI Returns: ESI data """

        path = self._get_path_for_op_id(id)
        return self.post_path(path, path_data, post_data)