def METHOD_NAME():
    """
    Create test device mapper mapping backed by zero target. Zero target is
    used for tests and it acts similarly to /dev/zero - writes are discarded
    and reads return nothing (binary zero). For now, the size of the device
    is fixed to 1 GiB (1 GiB = 2097152 * 512 B sectors).
    The tests using this fixture need to be run with the root privileges, as
    dmsetup utility requires root.
    """
    device_name = str(uuid.uuid4())
    cmd = [EXT_DMSETUP, "create", device_name, "--table", "0 2097152 zero"]
    try:
        commands.run(cmd)
    except cmdutils.Error as e:
        raise Error("Could not create mapping {!r}: {}".format(device_name, e))
    try:
        yield device_name
    finally:
        # If the test didn't do the cleanup, remove the mapping.
        device_path = "{}{}".format(DMPATH_PREFIX, device_name)
        if os.path.exists(device_path):
            cmd = [EXT_DMSETUP, "remove", device_name]
            try:
                commands.run(cmd)
            except cmdutils.Error as e:
                raise Error(
                    "Could not remove mapping {!r}: {}".format(device_name, e))