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. Note that Python 2 and 3 deal
    with strings differently.
    """
    if line.isspace():
        return True
    elif len(line.split()) >= 3:
        try:  # python 3 str
            if line.split()[0].isdecimal() and line.split()[1].isdecimal():
                return False
        except:  # python 2 str
            if (line.decode().split()[0].isdecimal() and
                    line.split()[1].decode().isdecimal()):
                return False
        return True
    else:
        return True