def is_degenerate(sides):
    """
    Check to see if a triangle is 'degenerate'.

    :param sides: list[*int] - the length of the three sides of a triangle
    :return bool - whether a triangle is degenerate or not

    >>> is_degenerate([1, 2, 3])
    True

    >>> is_degenerate([4, 5, 6])
    False

    The sum of the lengths of two sides equals that of the third is known as a degenerate triangle
    It has zero area and looks like a single line.
    """

    if sides[0] + sides[1] == sides[2]:
        return True

    if sides[1] + sides[2] == sides[0]:
        return True

    if sides[0] + sides[2] == sides[1]:
        return True

    return False