def make_size_label(size, var):
    """Takes a `size` and a flag `var` indicating if the size is variable and
    returns an HTML string describing it. E.g. "16+ bytes = 0x10+ (variable)"
    """
    template = '{} byte{} = {}' if var == 0 else '{}+ byte{} = {}+ <i>(variable)</i>'
    return template.format(size, '' if size == 1 else 's', hex(size))