def append(self, arg):
self.insert(len(self), arg)<EOL>
Append whitespace, an unparsed argument string, or an argument
        object.

        :param Arg arg: argument to add to the end of the list

        >>> arguments = TexArgs([RArg('arg0'), '[arg1]', '{arg2}'])
        >>> arguments.append('[arg3]')
        >>> arguments[3]
        OArg('arg3')
        >>> arguments.append(RArg('arg4'))
        >>> arguments[4]
        RArg('arg4')
        >>> len(arguments)
        5
        >>> arguments.append('\\n')
        >>> len(arguments)
        5
        >>> len(arguments.all)
        6