def METHOD_NAME(ch: channel.Channel) -> None:
    """
    Test whether blacklisted characters are properly caught.
    """
    ch._write_blacklist = [
        0x03,  # ETX  | End of Text / Interrupt
        0x04,  # EOT  | End of Transmission
        0x11,  # DC1  | Device Control One (XON)
        0x12,  # DC2  | Device Control Two
        0x13,  # DC3  | Device Control Three (XOFF)
        0x14,  # DC4  | Device Control Four
        0x15,  # NAK  | Negative Acknowledge
        0x16,  # SYN  | Synchronous Idle
        0x17,  # ETB  | End of Transmission Block
        0x1A,  # SUB  | Substitute / Suspend Process
        0x1C,  # FS   | File Separator
        0x7F,  # DEL  | Delete
        0x20,  # For test purposes: Space is illegal
    ]
    with pytest.raises(tbot.error.IllegalDataException):
        ch.sendline(" ")