@classmethod
def is_valid_chip_key(cls, key):
    """
        Valid chip keys must be strings formatted as:
        ``'<io_chain>-<chip_id>'``

        """
    if not super(cls, cls).is_valid_chip_key(key):
        return False
    if not isinstance(key, str):
        return False
    parsed_key = key.split('-')
    if not len(parsed_key) == 2:
        return False
    try:
        _ = int(parsed_key[0])
        _ = int(parsed_key[1])
    except ValueError:
        return False
    return True
