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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 close( self, exc_info: Union[ None, bool, BaseException, Tuple[ "Optional[Type[BaseException]]", Optional[BaseException], Optional[TracebackType], ], ] = False, ) -> None: """Close this stream. If ``exc_info`` is true, set the ``error`` attribute to the current exception from `sys.exc_info` (or if ``exc_info`` is a tuple, use that instead of `sys.exc_info`). """

        if not self.closed():
            if exc_info:
                if isinstance(exc_info, tuple):
                    self.error = exc_info[1]
                elif isinstance(exc_info, BaseException):
                    self.error = exc_info
                else:
                    exc_info = sys.exc_info()
                    if any(exc_info):
                        self.error = exc_info[1]
            if self._read_until_close:
                self._read_until_close = False
                self._finish_read(self._read_buffer_size, False)
            if self._state is not None:
                self.io_loop.remove_handler(self.fileno())
                self._state = None
            self.close_fd()
            self._closed = True
        self._signal_closed()