h are
    supported by the software, the attributes expressed. The exact result of
    the serialization depends on the behavior of the method specified by
    I{attributeRenderer}.

    For example, if your terminal is VT102 compatible, you might run
    this for a colorful variation on the "hello world" theme::

        from twisted.conch.insults.text import flatten, attributes as A
        from twisted.conch.insults.helper import CharacterAttribute
        print(flatten(
            A.normal[A.bold[A.fg.red['He'], A.fg.green['ll'], A.fg.magenta['o'], ' ',
                            A.fg.yellow['Wo'], A.fg.blue['rl'], A.fg.cyan['d!']]],
            CharacterAttribute()))

    @param output: Object returned by accessing attributes of the
        module-level attributes object.

    @param attrs: A formatting state instance used to determine how to
        serialize C{output}.

    @type attributeRenderer: C{str}
    @param attributeRenderer: Name of the method on I{attrs} that should be
        called to render the attributes during serialization. Defaults to
        C{'toVT102'}.

    @return: A string expressing the text and display attributes specified by
        L{output}.
    r?