descriptors.py 文件源码

def seek(self, position: int, whence: int = 0) -> None:
        """
        Seek the file at the given position.

        .. note:: The :exc:`io.UnsupportedOperation` will be raised if the underlying file-object is not
        :meth:`.seekable`.

        :param position: the position to seek on.
        :param whence: optional whence argument.

        """
        raise NotImplementedError('Seek operation is not supported by this object: %r' % self)  # pragma: no cover