def _iscomment(line):
    """
    Determine if a line is a comment line. A valid line contains at least three
    words, with the first two being integers.
    """
    if line.isspace():
        return True
    elif len(line.split()) >= 3:
        if line.split()[0].isdecimal() and line.split()[1].isdecimal():
            return False
        else:
            return True
    else:
        return True
