def extend(self, args):
for arg in args:<EOL><INDENT>self.append(arg)<EOL><DEDENT>
Extend mixture of unparsed argument strings, arguments objects, and
        whitespace.

        :param List[Arg] args: Arguments to add to end of the list

        >>> arguments = TexArgs([RArg('arg0'), '[arg1]', '{arg2}'])
        >>> arguments.extend(['[arg3]', RArg('arg4'), '\\t'])
        >>> len(arguments)
        5
        >>> arguments[4]
        RArg('arg4')