def get_binary_stream(name):
    """Returns a system stream for byte processing.

    :param name: the name of the stream to open.  Valid names are ``'stdin'``,
                 ``'stdout'`` and ``'stderr'``
    """
    opener = binary_streams.get(name)
    if opener is None:
        raise TypeError(f"Unknown standard stream '{name}'")
    return opener()
Returns a system stream for byte processing.

    :param name: the name of the stream to open.  Valid names are ``'stdin'``,
                 ``'stdout'`` and ``'stderr'``
    
dynaconf/vendor/click/utils.py