def __getitem__(self, key):
value = super().__getitem__(key)<EOL>if isinstance(value, list):<EOL><INDENT>return TexArgs(value)<EOL><DEDENT>return value<EOL>
Standard list slicing.

        Returns TexArgs object for subset of list and returns an Arg object
        for single items.

        >>> arguments = TexArgs([RArg('arg0'), '[arg1]', '{arg2}'])
        >>> arguments[2]
        RArg('arg2')
        >>> arguments[:2]
        [RArg('arg0'), OArg('arg1')]