def is_valid_ecl(ecl: str) -> bool:
    """
    (Eye Color) - exactly one of: amb blu brn gry grn hzl oth.

    :return: Status of field (true = valid).
    :rtype: bool
    """
    colours = ["amb", "blu", "brn", "gry", "grn", "hzl", "oth"]
    if ecl not in colours:
        return False
    return True